Tension detection control method for scraper chain of scraper conveyor on high gangue working face

Abstract

The invention provides a high gangue working face scraper conveyor scraper chain tension detection control method, which relates to the technical field of scraper conveyor equipment, and comprises the following steps: acquiring a first distance between the scraper bottom surface of a scraper conveyor and a machine head bottom plate and a first pressure of the scraper on the machine head bottom plate; acquiring a second distance between a scraper of the scraper conveyor and the upper edge of the tail and a second pressure of the scraper on the upper edge of the tail; calculating the minimum tension of a scraper chain at the lower part of the current machine head according to the first pressure, and calculating the minimum tension of a scraper chain at the upper part of the current machine tail according to the second pressure; determining a target minimum tension range according to the chain specification; the tensioning state of the current scraper chain is determined according to the current minimum tension of the scraper chain on the lower portion of the machine head and the upper portion of the machine tail, the first interval, the second interval and the target minimum tension range; and the tensioning force of the scraper chain is adjusted according to the current tensioning state of the scraper chain. According to the scheme, automatic tensioning of the scraper chain of the scraper conveyor can be achieved, and abrasion of the scraper chain and chain ways of the machine head and the machine tail of the scraper conveyor is delayed.

Description

Technical Field

[0001] This invention relates to the field of scraper conveyor technology, and in particular to a method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face. Background Technology

[0002] Coal seams in various regions of my country are complex, with significant variations in thickness, dip angle, and geological structure. The gangue content of the working face has a particularly direct impact on the reliability of transport equipment. For example, in early mining operations at mines like Suancigou and Shangyuquan, resources were relatively good, with gangue content below 20%. Scraper conveyor equipment manufacturers typically upgraded the plates and optimized the castings to meet basic usage requirements. In recent years, however, with increased mining capacity in coal seams with better geological conditions and decreasing recoverable reserves, some domestic coal mines have entered a new development stage of mining coal seams with different geological conditions to tap deeper potential. In some working faces, the gangue content has reached over 30%, posing a severe challenge to the reliability of scraper conveyors. Furthermore, coal mines are increasingly demanding higher single-face output, with longer working faces and greater strike distances becoming the norm. This poses a risk that scraper conveyors may be unable to complete the transport tasks for the entire working face due to insufficient overload capacity. According to statistics from coal mines across the country, the number of coal mine faces with high gangue content will gradually increase in the future. The high gangue content of raw coal at the working face will cause accelerated wear on scraper conveyors, significantly reducing their service life. The tension of the scraper chain not only affects its normal operation and service life, but also promotes the wear of the scraper chain and the chain track with relative movement with it.

[0003] In practice, a scraper conveyor is a flexible body composed of a drive unit, a head section, a tail section, and multiple intermediate sections. The scraper chain forms a flexible closed loop by wrapping around the sprockets at the head and tail. The upper scraper chain runs on the middle plates of the head, tail, and intermediate sections, transporting raw coal from the tail towards the head, and unloading it at the head for transfer to other auxiliary equipment. The lower scraper chain wraps around the head sprocket and runs between the middle and bottom plates of the head, tail, and intermediate sections, and wraps around the tail sprocket on the middle plates of the head, tail, and intermediate sections. However, as an elastic deformable body, the scraper chain's tension changes with the load, and its elasticity also changes. During operation, the scraper chain is prone to becoming too loose or too tight, leading to jamming or increased wear, affecting the normal operation of the equipment. Summary of the Invention

[0004] In view of this, and to address the above shortcomings, it is necessary to propose a method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face, so as to achieve automatic tensioning of the scraper chain and delay the wear of the scraper chain and the chain tracks at the head and tail of the scraper conveyor.

[0005] This invention provides a method for detecting and controlling the tension of the scraper chain in a scraper conveyor for high-gangue working faces, comprising:

[0006] The first distance between the bottom surface of the scraper and the bottom plate of the machine head when the scraper of the scraper conveyor passes through is obtained, as well as the first pressure of the scraper on the bottom plate of the machine head;

[0007] The second distance between the scraper of the scraper conveyor and the upper edge of the tail section when the scraper passes through, and the second pressure of the scraper on the upper edge of the tail section;

[0008] The minimum tension of the scraper chain at the lower part of the machine head is calculated based on the first pressure, and the minimum tension of the scraper chain at the upper part of the machine tail is calculated based on the second pressure.

[0009] Based on the chain specifications of the scraper conveyor, determine the target minimum tension range of the scraper chain at the lower part of the head and the upper part of the tail.

[0010] The tension state of the scraper chain is determined based on the minimum tension of the scraper chain at the lower part of the machine head, the minimum tension of the scraper chain at the upper part of the machine tail, the first gap, the second gap, and the target minimum tension range.

[0011] The tension of the scraper chain is adjusted in real time according to the current tension state of the scraper chain.

[0012] Preferably, the first Hall distance sensor for detecting the first distance between the bottom of the scraper and the bottom plate of the machine head is installed on the uphill section of the bottom plate of the machine head, and the distance between the scraper and the bottom plate does not exceed the range of the Hall distance sensor when the scraper chain is tensioned.

[0013] The first pressure sensor, used to detect the first pressure of the scraper on the bottom plate of the machine head, is installed on the bottom plate of the machine head at the transition position from the uphill section to the horizontal section.

[0014] The second Hall distance sensor used to detect the second distance between the scraper and the upper edge of the tailpiece, and the second pressure sensor used to detect the second pressure of the scraper on the upper edge of the tailpiece, are both installed on the downhill section of the upper edge of the tailpiece.

[0015] Preferably, the step of calculating the minimum tension of the scraper chain at the lower part of the machine head based on the first pressure includes: calculating the minimum tension of the scraper chain at the lower part of the machine head using the following formula:

[0016] F1 = N1 * cos(α / 2)

[0017] Wherein, F1 is the minimum tension of the scraper chain at the lower part of the current machine head, N1 is the first pressure, and α is the wrap angle of the scraper at the pressure detection point of the machine head;

[0018] The step of calculating the minimum tension of the upper scraper chain at the tail section based on the second pressure includes: calculating the minimum tension of the upper scraper chain at the tail section using the following formula:

[0019] F2 = N2 * cos(β / 2)

[0020] Wherein, F2 is the minimum tension of the upper scraper chain at the current tail, N2 is the second pressure, and β is the wrap angle of the scraper at the tail pressure detection point.

[0021] Preferably, determining the current tension state of the scraper chain includes:

[0022] If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both within the target minimum tension range, and the first gap and the second gap are both less than the preset maximum allowable gap, then it is determined that the current scraper chain tension is normal.

[0023] If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both greater than the upper limit of the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too high.

[0024] If the minimum tension of the scraper chain at the lower part of the current machine head and the minimum tension of the scraper chain at the upper part of the current machine tail are both less than the lower limit of the target minimum tension range, the first spacing is less than the first preset spacing threshold, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too low; wherein, the first preset spacing threshold and the second preset spacing threshold are both less than the preset maximum allowable spacing, and the first preset spacing threshold is less than the second preset spacing threshold;

[0025] If the minimum tension of the scraper chain at the lower part of the machine head is greater than the upper limit of the target minimum tension range, and the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the scraper chain at the machine head.

[0026] If the minimum tension of the scraper chain at the lower part of the machine head is less than the lower limit of the target minimum tension range, the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, the first gap is less than the first preset gap threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tension of the scraper chain at the machine head.

[0027] If the current minimum tension of the upper scraper chain at the tail is greater than the upper limit of the target minimum tension range, and the current minimum tension of the lower scraper chain at the head is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the tail scraper chain.

[0028] If the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, the minimum tension of the lower scraper chain at the current head is within the target minimum tension range, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tail scraper chain tension.

[0029] Preferably, adjusting the scraper chain tension according to the current tension state of the scraper chain includes:

[0030] When the tension of the scraper chain is too high, the tail cylinder is controlled to retract to reduce the tension to the target minimum tension range;

[0031] When the tension of the scraper chain is too low, the tail cylinder is extended to increase the tension to the target minimum tension range.

[0032] When the tension of the scraper chain at the machine head is too high, the speed of the machine head drive motor is increased to reduce the tension at the lower part of the machine head to the target minimum tension range.

[0033] When the tension of the scraper chain at the machine head is too low, the speed of the machine head drive motor is reduced to increase the tension at the lower part of the machine head to the target minimum tension range.

[0034] When the tension of the tail scraper chain is too high, the tail cylinder is controlled to retract to reduce the tension of the upper tail scraper chain to the target minimum tension range.

[0035] When the tension of the tail scraper chain is too low, the tail cylinder is extended and the speed of the tail drive motor is reduced to increase the tension of the upper tail scraper chain to the target minimum tension range.

[0036] Preferably, after controlling the speed of the machine head drive motor to increase to reduce the tension at the lower part of the machine head to the target minimum tension range when the tension of the scraper chain at the machine head is too high, the method further includes:

[0037] The head drive motor is controlled to slow down to match the speed of the tail drive motor. When the scraper conveyor runs to the point where the minimum tension of the upper scraper chain at the current tail is greater than the upper limit of the target minimum tension range, the tail cylinder is controlled to retract to reduce the tension of the upper scraper chain at the tail to the target minimum tension range.

[0038] Preferably, after controlling the speed of the machine head drive motor to decrease to increase the tension at the lower part of the machine head to the target minimum tension range when the tension of the scraper chain of the machine head is too low, the method further includes:

[0039] The head drive motor is accelerated to match the speed of the tail drive motor, and when the scraper conveyor runs to the point where the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, the tail cylinder is extended to increase the tension of the upper scraper chain at the tail to the target minimum tension range.

[0040] Preferably, after controlling the tail cylinder to extend and simultaneously reducing the speed of the tail drive motor when the tail scraper chain tension is too low, in order to increase the upper tail scraper chain tension to the target minimum tension range, the method further includes:

[0041] Control the head drive motor to increase its speed to match the speed of the tail drive motor.

[0042] Preferably, the first preset duration is 15 seconds.

[0043] Preferably, when starting the scraper conveyor, the tail cylinder is extended and the first pressure is kept within a preset pressure range.

[0044] In the method for detecting and controlling the tension of the scraper chain of a scraper conveyor in a high-gangue working face provided by this invention, the following steps are taken: First, the first distance between the bottom surface of the scraper and the head plate and the first pressure of the scraper on the head plate are obtained when the scraper of the scraper passes through. Second, the second distance between the scraper and the upper edge of the tail section and the second pressure of the scraper on the upper edge of the tail section are obtained when the scraper of the scraper passes through. Then, the minimum tension of the scraper chain at the lower part of the head is calculated based on the first pressure, and the minimum tension of the scraper chain at the upper part of the tail is calculated based on the second pressure. Further, the target minimum tension range of the scraper chain at the lower part of the head and the upper part of the tail is determined according to the chain specifications of the scraper conveyor. The tension state of the scraper chain is determined based on the minimum tension of the scraper chain at the lower part of the head, the minimum tension of the scraper chain at the upper part of the tail, the first distance, the second distance, and the target minimum tension range. Finally, the tension of the scraper chain is adjusted in real time according to the current tension state of the scraper chain. Therefore, this solution monitors the distance between the scraper and the bottom plate of the machine head, as well as the pressure exerted by the scraper on the bottom plate, in real time. It also monitors the distance between the scraper and the upper edge of the tailpiece, and the pressure exerted by the scraper on the upper edge of the tailpiece, using the monitoring results to determine the current tension of the scraper chain and then taking corresponding measures to adjust the tension. This automatic adjustment of the scraper chain tension based on its dynamic changes solves the problem of the scraper chain becoming too loose or too tight during operation. This reduces scraper chain jamming and wear, ensuring normal equipment operation and extending the equipment's service life. Attached Figure Description

[0045] Figure 1 This is a flowchart of a method for detecting and controlling the tension of a scraper chain in a scraper conveyor for a high-gangue working face, provided as an embodiment of the present invention.

[0046] Figure 2 This is a diagram showing the chain tension distribution of a scraper conveyor.

[0047] Figure 3 This is a diagram showing the tension test of the scraper chain at the head of a scraper conveyor.

[0048] Figure 4 This is a diagram showing the tension detection of the scraper chain at the tail end of a scraper conveyor.

[0049] Figure 5 This is a schematic diagram of the pressure detection angle of the scraper chain at the lower part of the machine head.

[0050] Figure 6 This is a schematic diagram of the pressure detection angle of the upper scraper chain at the tail of the machine.

[0051] In the figure: First Hall ranging sensor 1, first pressure sensor 2, second Hall ranging sensor 3, second pressure sensor 4. Detailed Implementation

[0052] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] like Figure 1 As shown in the figure, this embodiment of the invention provides a method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face. The method may include the following steps:

[0054] Step 101: Obtain the first distance between the bottom surface of the scraper and the bottom plate of the machine head when the scraper of the scraper conveyor passes through, and the first pressure of the scraper on the bottom plate of the machine head;

[0055] Step 102: Obtain the second distance between the scraper of the scraper conveyor and the upper edge of the tail section when the scraper passes through, and the second pressure of the scraper on the upper edge of the tail section;

[0056] Step 103: Calculate the minimum tension of the scraper chain at the lower part of the machine head based on the first pressure, and calculate the minimum tension of the scraper chain at the upper part of the machine tail based on the second pressure;

[0057] Step 104: Determine the target minimum tension range of the scraper chain at the lower part of the head and the upper part of the tail according to the chain specifications of the scraper conveyor;

[0058] Step 105: Determine the tension state of the current scraper chain based on the current minimum tension of the scraper chain at the lower part of the machine head, the current minimum tension of the scraper chain at the upper part of the machine tail, the first gap, the second gap, and the target minimum tension range;

[0059] Step 106: Adjust the tension of the scraper chain in real time according to the current tension state of the scraper chain.

[0060] In this embodiment, the distance between the scraper and the bottom plate of the machine head, as well as the pressure of the scraper on the bottom plate, are monitored in real time. Similarly, the distance between the scraper and the upper edge of the tailpiece, and the pressure of the scraper on the upper edge of the tailpiece, are also monitored in real time. Based on these monitoring results, the current tension of the scraper chain is determined, and corresponding measures are taken to adjust the tension. This automatic adjustment of the scraper chain tension according to its dynamic changes solves the problem of the scraper chain becoming too loose or too tight during operation. This reduces scraper chain jamming and wear, ensuring normal equipment operation and extending the equipment's service life.

[0061] For step 101, obtain the first distance between the bottom surface of the scraper of the scraper conveyor and the bottom plate of the head when the scraper of the scraper conveyor passes through, and the first pressure of the scraper on the bottom plate of the head; and for step 102, obtain the second distance between the scraper of the scraper conveyor and the upper edge of the tail section when the scraper of the scraper conveyor passes through, and the second pressure of the scraper on the upper edge of the tail section.

[0062] like Figure 2 As shown, the scraper chain of the scraper conveyor is driven simultaneously by the head sprocket and the tail sprocket. During the raw coal transportation process, the tension of the upper scraper chain gradually increases from the tail to the head, with the tension being the lowest at the tail and the highest at the head. The tension of the lower scraper chain gradually decreases from the tail to the head, with the tension being the lowest at the head and the highest at the tail. The maximum tension of the upper scraper chain at the head is determined by the load, the weight of the upper scraper chain, and the running frictional resistance. The maximum tension of the lower scraper chain at the tail is determined by the weight of the lower scraper chain and the running frictional resistance. The minimum tension of the upper scraper chain at the tail and the lower scraper chain at the head can be adjusted by changing the center distance between the head and tail sprockets through tail extension and retraction. Therefore, it is necessary to consider detecting the tension of the lower scraper chain at the head (minimum tension point) and the tension of the upper scraper chain at the tail (minimum tension point).

[0063] Specifically, such as Figure 3 As shown, when detecting the tension of the scraper chain at the head of the scraper conveyor, a first Hall effect distance sensor 1, used to detect the first distance between the scraper bottom surface and the head plate, is installed on the uphill section of the head plate. With the scraper chain tensioned, the distance between the scraper and the plate does not exceed the range of the Hall effect distance sensor. This allows the first Hall effect distance sensor 1 to monitor the first distance A between the scraper bottom surface and the head plate in real time as the scraper passes through. Additionally, a first pressure sensor 2, used to detect the first pressure exerted by the scraper on the head plate, is installed on the head plate at the transition point from the uphill section to the horizontal section. This allows the first pressure N1 exerted by the scraper on the head plate in real time as the scraper passes through.

[0064] Similarly, such as Figure 4 As shown, when detecting the tension of the scraper chain at the tail of the scraper conveyor, a second Hall distance sensor 3 for detecting the second distance between the scraper and the upper edge of the tail conveyor, and a second pressure sensor 4 for detecting the second pressure of the scraper on the upper edge of the tail conveyor are both installed on the downhill section of the upper edge of the tail conveyor. Thus, the second Hall distance sensor 3 is used to monitor in real time the second distance B between the scraper and the upper edge of the tail conveyor, and the second pressure N2 of the scraper on the upper edge of the tail conveyor.

[0065] Step 103: Calculate the minimum tension of the scraper chain at the lower part of the machine head based on the first pressure, and calculate the minimum tension of the scraper chain at the upper part of the machine tail based on the second pressure.

[0066] This step involves calculating the tension of the scraper chain at the lower part of the scraper conveyor head and the tension of the scraper chain at the upper part of the scraper conveyor tail, respectively. Specifically, as shown... Figure 5 As shown, when calculating the minimum tension of the scraper chain at the lower part of the machine head based on the first pressure, it can be obtained by F1=N1*cos(α / 2); where F1 is the minimum tension of the scraper chain at the lower part of the machine head, N1 is the first pressure, and α is the wrap angle of the scraper at the pressure detection point at the machine head.

[0067] Similarly, such as Figure 6 As shown, when calculating the minimum tension of the upper scraper chain at the tail of the machine based on the second pressure, it can be obtained by F2=N2*cos(β / 2); where F2 is the minimum tension of the upper scraper chain at the tail of the machine, N2 is the second pressure, and β is the wrap angle of the scraper at the pressure detection point at the tail of the machine.

[0068] Step 104: Determine the target minimum tension range of the scraper chain at the lower part of the head and the upper part of the tail according to the chain specifications of the scraper conveyor.

[0069] Because the minimum tension varies between chains of different specifications, the tension threshold range is determined based on the chain specifications of the scraper conveyor. Specifically, the minimum tension ranges for different chain specifications are shown in Table 1 below:

[0070] Table 1

[0071]

[0072] Thus, based on the current chain specifications of the scraper conveyor, the corresponding target minimum tension range can be determined using Table 1 above.

[0073] Step 105: Determine the tension state of the current scraper chain based on the minimum tension of the current scraper chain at the lower part of the machine head, the minimum tension of the current scraper chain at the upper part of the machine tail, the first gap, the second gap, and the target minimum tension range.

[0074] This step aims to determine the current tension state of the scraper chain based on the current minimum tension of the scraper chain at the lower part of the machine head, the current minimum tension of the scraper chain at the upper part of the machine tail, the first gap, the second gap, and the target minimum tension range. Specifically, the tension state of the scraper chain can be determined as follows:

[0075] If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both within the target minimum tension range, and the first gap and the second gap are both less than the preset maximum allowable gap, then it is determined that the current scraper chain tension is normal.

[0076] If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both greater than the upper limit of the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too high.

[0077] If the minimum tension of the scraper chain at the lower part of the current machine head and the minimum tension of the scraper chain at the upper part of the current machine tail are both less than the lower limit of the target minimum tension range, the first spacing is less than the first preset spacing threshold, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too low; wherein, the first preset spacing threshold and the second preset spacing threshold are both less than the preset maximum allowable spacing, and the first preset spacing threshold is less than the second preset spacing threshold;

[0078] If the minimum tension of the scraper chain at the lower part of the machine head is greater than the upper limit of the target minimum tension range, and the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the scraper chain at the machine head.

[0079] If the minimum tension of the scraper chain at the lower part of the machine head is less than the lower limit of the target minimum tension range, the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, the first gap is less than the first preset gap threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tension of the scraper chain at the machine head.

[0080] If the current minimum tension of the upper scraper chain at the tail is greater than the upper limit of the target minimum tension range, and the current minimum tension of the lower scraper chain at the head is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the tail scraper chain.

[0081] If the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, the minimum tension of the lower scraper chain at the current head is within the target minimum tension range, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tail scraper chain tension.

[0082] In this embodiment, the maximum allowable spacing of the scraper chain is preset to a maximum allowable distance, for example, 60mm. Of course, different preset maximum allowable spacings can be set for the head and tail of the machine. For example, the preset maximum allowable spacing for the head can be 60mm, and the preset maximum allowable spacing for the tail can be 50mm. The first preset duration can be 15 seconds. Furthermore, if the scraper chain briefly gets stuck, i.e., if tension exceeds the limit within 0-15 seconds, it can be automatically ignored, and the hydraulic cylinder will not operate.

[0083] When the scraper conveyor is running normally, the distance between the scraper at the head and the bottom plate of the head is usually between 10mm and 60mm, and the distance between the scraper at the tail and the upper edge of the tail is usually between 15mm and 50mm. Therefore, the first preset distance threshold can be set to 15mm, and the second preset distance threshold can be set to 45mm.

[0084] Step 106: Adjust the tension of the scraper chain in real time according to the current tension state of the scraper chain.

[0085] When the scraper conveyor chain is automatically tensioned, the center distance between the head and tail sprockets is adjusted by extending and retracting the automatic telescopic cylinder at the tail end. In this embodiment, the aim is to adjust the scraper chain tension in real time according to the current tension state. Specifically, this can be achieved in the following way:

[0086] (1) When the scraper chain is tensioned normally, the tail extension cylinder remains stationary.

[0087] (2) When the tension of the scraper chain is too high, control the tail cylinder to retract, reduce the center distance, and thus reduce the tension to the target minimum tension range;

[0088] (3) When the tension of the scraper chain is too low, control the tail cylinder to extend, increase the center distance, and thus increase the tension to the target minimum tension range;

[0089] (4) When the tension of the scraper chain of the machine head is too high, the speed of the machine head drive motor is increased to reduce the tension at the bottom of the machine head to the target minimum tension range;

[0090] In this embodiment, after the tension at the lower part of the conveyor head reaches the target minimum tension range, synchronization is further considered. Specifically, the speed of the head drive motor can be reduced to match the speed of the tail drive motor. After the scraper conveyor has been running for a period of time, if the minimum tension of the upper scraper chain at the current tail is greater than the upper limit of the target minimum tension range and the duration is greater than 15 seconds, the tail cylinder is controlled to retract, reducing the center distance and thus lowering the tension of the upper scraper chain at the tail to the target minimum tension range.

[0091] (5) When the tension of the scraper chain of the machine head is too low, the speed of the machine head drive motor is reduced to increase the tension of the lower part of the machine head to the target minimum tension range.

[0092] In this embodiment, after the tension at the lower part of the conveyor head reaches the target minimum tension range, a synchronization restoration operation is further performed. Specifically, the speed of the head drive motor can be increased to match the speed of the tail drive motor. After the scraper conveyor has been running for a period of time, when the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, and the duration is greater than 15 seconds, the tail cylinder is extended to increase the center distance, thereby increasing the tension of the upper scraper chain at the tail to the target minimum tension range.

[0093] (6) When the tension of the tail scraper chain is too high, control the tail cylinder to retract, reduce the center distance, and thus reduce the tension of the upper tail scraper chain to the target minimum tension range.

[0094] (7) When the tension of the tail scraper chain is too low, the tail cylinder is extended to increase the center distance, and the speed of the tail drive motor is reduced to increase the tension of the upper tail scraper chain to the target minimum tension range.

[0095] In this embodiment, when the tension of the scraper chain at the upper tail reaches the target minimum tension range, a synchronization restoration operation is further performed. Specifically, the speed of the head drive motor can be controlled to match the speed of the tail drive motor.

[0096] It should be noted that the strategy for setting the scraper chain tension is as follows: the closer the current of the head drive motor is to the rated current, the closer the tension should be to the lower limit. The greater the difference between the head drive motor current and the rated current, the closer the tension should be to the upper limit.

[0097] Furthermore, before the scraper conveyor starts, as the automatic telescopic cylinder extends to increase the sprocket center distance, the scraper chain gradually tensions from the tail to the head. At this time, the tension of the upper and lower scraper chains at the tail is at its maximum, and the tension at the upper and lower scraper chains at the head is at its minimum. Specifically, the tension of the scraper chain before startup is judged based on the minimum tension F1 of the lower scraper chain at the head. The automatic telescopic cylinder at the tail is controlled to extend, so that F1 reaches the range of 0.5 to 0.8 kN. A larger value is used for larger-specification chains, and a smaller value is used for smaller-specification chains.

[0098] In summary, the scraper chain tension detection and control method for scraper conveyors in high gangue working faces provided by this invention provides a method for detecting and controlling the minimum tension of the scraper chain at the head and tail of the scraper conveyor, realizing automatic tensioning of the scraper chain and control of the minimum tension of the scraper chain at the head and tail, thus delaying the wear of the scraper chain and the chain tracks at the head and tail of the scraper conveyor.

[0099] This specification also provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to perform the methods in any of the embodiments of the specification.

[0100] This specification also provides a computing device, including a memory and a processor, wherein the memory stores executable code, and when the processor executes the executable code, it implements the method in any of the embodiments of the specification.

[0101] The device embodiments provided by the present invention are based on the same inventive concept as the method embodiments in this specification. For details, please refer to the description in the method embodiments of this specification, which will not be repeated here.

[0102] The modules or units in the device of this invention can be merged, divided, and deleted according to actual needs. The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the processes of the above embodiments and making equivalent changes according to the claims of this invention still fall within the scope of the invention.

Claims

1. A method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face, characterized in that, include: The first distance between the bottom surface of the scraper and the bottom plate of the machine head when the scraper of the scraper conveyor passes through is obtained, as well as the first pressure of the scraper on the bottom plate of the machine head; The second distance between the scraper of the scraper conveyor and the upper edge of the tail section when the scraper passes through, and the second pressure of the scraper on the upper edge of the tail section; The minimum tension of the scraper chain at the lower part of the machine head is calculated based on the first pressure, and the minimum tension of the scraper chain at the upper part of the machine tail is calculated based on the second pressure. Based on the chain specifications of the scraper conveyor, determine the target minimum tension range of the scraper chain at the lower part of the head and the upper part of the tail. The tension state of the scraper chain is determined based on the minimum tension of the scraper chain at the lower part of the machine head, the minimum tension of the scraper chain at the upper part of the machine tail, the first gap, the second gap, and the target minimum tension range. The tension of the scraper chain is adjusted in real time according to the current tension state of the scraper chain.

2. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-grade gangue working face according to claim 1, characterized in that, The first Hall effect distance sensor for detecting the first distance between the bottom of the scraper and the bottom plate of the machine head is installed on the uphill section of the bottom plate of the machine head, and the distance between the scraper and the bottom plate does not exceed the range of the Hall effect distance sensor when the scraper chain is tensioned. The first pressure sensor, used to detect the first pressure of the scraper on the bottom plate of the machine head, is installed on the bottom plate of the machine head at the transition position from the uphill section to the horizontal section. The second Hall distance sensor used to detect the second distance between the scraper and the upper edge of the tail section, and the second pressure sensor used to detect the second pressure of the scraper on the upper edge of the tail section, are both installed on the downhill section of the upper edge of the tail section.

3. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to claim 1, characterized in that, The step of calculating the minimum tension of the scraper chain at the lower part of the machine head based on the first pressure includes: calculating the minimum tension of the scraper chain at the lower part of the machine head using the following formula: F1 = N1 * cos(α / 2) Wherein, F1 is the minimum tension of the scraper chain at the lower part of the current machine head, N1 is the first pressure, and α is the wrap angle of the scraper at the pressure detection point of the machine head; The step of calculating the minimum tension of the upper scraper chain at the tail section based on the second pressure includes: calculating the minimum tension of the upper scraper chain at the tail section using the following formula: F2 = N2 * cos(β / 2) Wherein, F2 is the minimum tension of the upper scraper chain at the current tail, N2 is the second pressure, and β is the wrap angle of the scraper at the tail pressure detection point.

4. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-quality gangue working face according to claim 1, characterized in that, Determining the current tension state of the scraper chain includes: If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both within the target minimum tension range, and the first gap and the second gap are both less than the preset maximum allowable gap, then it is determined that the current scraper chain tension is normal. If the minimum tension of the scraper chain at the lower part of the machine head and the minimum tension of the scraper chain at the upper part of the machine tail are both greater than the upper limit of the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too high. If the minimum tension of the scraper chain at the lower part of the current machine head and the minimum tension of the scraper chain at the upper part of the current machine tail are both less than the lower limit of the target minimum tension range, the first spacing is less than the first preset spacing threshold, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain tension is too low; wherein, the first preset spacing threshold and the second preset spacing threshold are both less than the preset maximum allowable spacing, and the first preset spacing threshold is less than the second preset spacing threshold; If the minimum tension of the scraper chain at the lower part of the machine head is greater than the upper limit of the target minimum tension range, and the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the scraper chain at the machine head. If the minimum tension of the scraper chain at the lower part of the machine head is less than the lower limit of the target minimum tension range, the minimum tension of the scraper chain at the upper part of the machine tail is within the target minimum tension range, the first gap is less than the first preset gap threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tension of the scraper chain at the machine head. If the current minimum tension of the upper scraper chain at the tail is greater than the upper limit of the target minimum tension range, and the current minimum tension of the lower scraper chain at the head is within the target minimum tension range, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of excessive tension of the tail scraper chain. If the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, the minimum tension of the lower scraper chain at the current head is within the target minimum tension range, the second spacing is greater than the second preset spacing threshold, and the duration is greater than the first preset duration, then it is determined that the current scraper chain is in a state of low tail scraper chain tension.

5. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to claim 4, characterized in that, The step of adjusting the scraper chain tension in real time according to the current tension state of the scraper chain includes: When the tension of the scraper chain is too high, the tail cylinder is controlled to retract to reduce the tension to the target minimum tension range; When the tension of the scraper chain is too low, the tail cylinder is extended to increase the tension to the target minimum tension range. When the tension of the scraper chain at the machine head is too high, the speed of the machine head drive motor is increased to reduce the tension at the lower part of the machine head to the target minimum tension range. When the tension of the scraper chain at the machine head is too low, the speed of the machine head drive motor is reduced to increase the tension at the lower part of the machine head to the target minimum tension range. When the tension of the tail scraper chain is too high, the tail cylinder is controlled to retract to reduce the tension of the upper tail scraper chain to the target minimum tension range. When the tension of the tail scraper chain is too low, the tail cylinder is extended and the speed of the tail drive motor is reduced to increase the tension of the upper tail scraper chain to the target minimum tension range.

6. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to claim 5, characterized in that, After controlling the speed of the machine head drive motor to increase to reduce the tension at the lower part of the machine head to the target minimum tension range when the tension of the scraper chain at the machine head is too high, the process further includes: The head drive motor is controlled to slow down to match the speed of the tail drive motor. When the scraper conveyor runs to the point where the minimum tension of the upper scraper chain at the current tail is greater than the upper limit of the target minimum tension range, the tail cylinder is controlled to retract to reduce the tension of the upper scraper chain at the tail to the target minimum tension range.

7. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to claim 5, characterized in that, After controlling the speed of the machine head drive motor to decrease to increase the tension at the lower part of the machine head to the target minimum tension range when the tension of the scraper chain at the machine head is too low, the process further includes: The head drive motor is accelerated to match the speed of the tail drive motor, and when the scraper conveyor runs to the point where the minimum tension of the upper scraper chain at the current tail is less than the lower limit of the target minimum tension range, the tail cylinder is extended to increase the tension of the upper scraper chain at the tail to the target minimum tension range.

8. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-quality gangue working face according to claim 5, characterized in that, When the tension of the tail scraper chain is too low, the tail cylinder is extended while the speed of the tail drive motor is reduced to increase the tension of the upper tail scraper chain to the target minimum tension range. The process further includes: Control the head drive motor to increase its speed to match the speed of the tail drive motor.

9. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to claim 4, characterized in that, The first preset duration is 15 seconds.

10. The method for detecting and controlling the tension of the scraper chain in a scraper conveyor for a high-gangue working face according to any one of claims 1 to 9, characterized in that, When starting the scraper conveyor, control the tail cylinder to extend and keep the first pressure within the preset pressure range.

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