Automatic chain tensioning method

Abstract

The invention provides an automatic chain tensioning method which is used for a scraper conveyor, the scraper conveyor comprises a telescopic oil cylinder, a machine tail, a middle groove and a machine head, the machine tail, the middle groove and the machine head are sequentially connected in the coal conveying direction, chain wheels are arranged at the machine head and the machine tail, and the chain wheels are used for winding a chain; the method comprises the steps that the real-time transportation volume of the scraper conveyor is obtained; calculating the pre-tightening force of the chain and the theoretical pressure intensity of the telescopic oil cylinder based on the real-time transportation volume; controlling the telescopic oil cylinder to move based on the theoretical pressure intensity; detecting the instant tension of the chain; and comparing the real-time tension with the pre-tightening force in real time, and adjusting the working state of the telescopic oil cylinder based on a comparison result. Therefore, the tensioning degree of the chain can be accurately controlled, the problems of accumulation, chain breakage or chain clamping and the like caused by the fact that the chain is too loose are avoided, excessive abrasion and damage of equipment caused by the fact that the chain is too tight are also prevented, and the stability and reliability of operation of the scraper conveyor are greatly improved.

Description

Technical Field

[0001] The present application belongs to the technical field of scraper conveyors, and in particular relates to an automatic chain tensioning method. Background Art

[0002] As a key transportation equipment for the fully mechanized mining face in underground coal mines, the scraper conveyor works on the principle that the torque generated by the motor is transmitted to the sprocket shaft group through the reducer, thereby pulling the scraper chain to move, thus building a closed chain traction system. Under the action of this system, the coal is brought from the tail of the machine to the head of the machine, and after reaching the head of the machine, it is transferred to the transfer machine, thereby achieving the purpose of transporting the coal out of the working face.

[0003] Among them, the scraper chain is an elastic body, which will produce elastic elongation when subjected to tension during operation. This elongation will cause the chain to become loose at the part where it is engaged and separated from the sprocket, and may even cause accumulation, leading to chain breakage and chain jamming accidents. Therefore, during the use of the scraper conveyor, a certain pre-tightening force needs to be applied to the chain. However, in actual use, the elastic elongation of the chain is often difficult to effectively control, which ultimately makes it difficult for the chain to be in an ideal tension state. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present application is to provide a method for automatic chain tensioning, which adjusts the working state of the telescopic cylinder by comparing the instantaneous tension and pre-tension of the chain in real time, ensuring that the chain is always in a relatively ideal tensioned state, thereby reducing equipment failures and operation fluctuations caused by improper chain tensioning.

[0005] In order to solve the above problems, the present application provides a chain automatic tensioning method for a scraper conveyor, wherein the scraper conveyor comprises a telescopic oil cylinder and a tail, a middle trough and a head connected in sequence along the coal transportation direction, and sprockets are provided at the head and the tail, and the sprockets are used to wind the chain; the method comprises:

[0006] Obtaining the real-time transport volume of the scraper conveyor;

[0007] Calculating the preload force of the chain and the theoretical pressure strength of the telescopic cylinder based on the real-time transport volume;

[0008] Controlling the movement of the telescopic cylinder based on the theoretical pressure intensity;

[0009] detecting instantaneous tension of the chain;

[0010] The instantaneous tension and the preload force are compared in real time, and the working state of the telescopic cylinder is adjusted based on the comparison result.

[0011] Optionally, the preload force of the chain complies with the formula:

[0012]

[0013] In the formula, T0 is the preload of the chain; S1 is the theoretical tension of the chain at the winding-out point of the sprocket arranged at the tail of the machine; S2 is the theoretical tension of the chain at the winding-in point of the sprocket arranged at the tail of the machine; S3 is the theoretical tension of the chain at the winding-out point of the sprocket arranged at the head of the machine; S4 is the theoretical tension of the chain at the winding-in point of the sprocket arranged at the head of the machine.

[0014] Optionally, the value range of S1 is 2 to 3 kN;

[0015] S2 complies with the formula:

[0016]

[0017] In the formula, k r is the resistance coefficient of the chain passing through the sprocket;

[0018] S3 complies with the formula:

[0019] S3=S2-Lq0(μ * cosβ±sinβ)

[0020] Wherein, L is the laying length of the scraper conveyor; q0 is the weight per unit length of the chain; μ * is the equivalent friction coefficient of the lower chain of the scraper conveyor; β is the inclination angle of the working surface of the scraper conveyor;

[0021] S4 complies with the formula:

[0022] S4=S1+Lq(μ * cosβ±sinβ)

[0023] Where, q is the coal load per unit length of the scraper conveyor; μ * is the equivalent friction coefficient of the upper chain of the scraper conveyor.

[0024] Optionally, the equivalent friction coefficient μ of the lower chain of the scraper conveyor is * Conforms to the formula:

[0025]

[0026] The equivalent friction coefficient μ of the upper chain of the scraper conveyor * Conforms to the formula:

[0027]

[0028] Wherein, V is the movement speed of the chain; γ is the efficiency loss of the telescopic cylinder; h is the coal loading height of the scraper conveyor;

[0029] The coal loading height h of the scraper conveyor complies with the formula:

[0030]

[0031] Wherein, B is the width of the middle groove; h1 is the depth of the middle groove;

[0032] The coal load per unit length q of the scraper conveyor conforms to the formula:

[0033]

[0034] Wherein, W is the real-time transport volume of the scraper conveyor; g is the acceleration of gravity.

[0035] Optionally, the middle troughs are provided in plurality, and a coal quantity scanner is provided at each of the middle troughs in a one-to-one correspondence, and the coal quantity scanner is used to obtain the real-time transport volume of the scraper conveyor;

[0036] The interval between two adjacent coal quantity scanners is the slot length of the middle slot.

[0037] Optionally, the theoretical pressure strength of the telescopic cylinder complies with the formula:

[0038]

[0039] In the formula, n is the number of the telescopic cylinders; D is the inner diameter of the telescopic cylinder; γ is the efficiency loss of the telescopic cylinder.

[0040] Optionally, the instantaneous tension of the chain complies with the formula:

[0041]

[0042] In the formula, is the instantaneous tension of the chain; is the actual tension of the chain at the winding-out point of the sprocket arranged at the tail of the machine; is the actual tension of the chain at the winding point of the sprocket provided at the tail of the machine; is the actual tension of the chain at the winding-out point of the sprocket provided at the machine head; is the actual tension of the chain at the winding point of the sprocket provided at the machine head;

[0043] in, and All conform to the formula:

[0044] F=AEε

[0045] Wherein, F is tension; A is the cross-sectional area of ​​the chain; E is the elastic modulus of the chain; ε is the strain value of the chain.

[0046] Optionally, the scraper conveyor further comprises a tension detection module, which is used to sense the strain value of the chain at the winding-out point and the winding-in point relative to the sprocket arranged at the tail and the winding-out point and the winding-in point of the sprocket arranged at the head;

[0047] Wherein, the chain includes several steel rings, the tension detection module includes at least two wireless receivers, several wireless collectors and several strain sensors, at least two of the wireless receivers are respectively arranged at the head and the tail, and several of the wireless collectors and several of the strain sensors are arranged one by one on several of the steel rings.

[0048] Optionally, comparing the instantaneous tension with the preload in real time and adjusting the working state of the telescopic cylinder based on the comparison result includes:

[0049] Comparing the instantaneous tension with a preset setting interval in real time;

[0050] When the instantaneous tension is within the preset setting interval, the extension amount of the telescopic cylinder is kept unchanged; when the instantaneous tension is greater than the upper limit value of the preset setting interval, the extension amount of the telescopic oil cylinder is controlled to decrease; when the instantaneous tension is less than the lower limit value of the preset setting interval, the extension amount of the telescopic oil cylinder is controlled to increase.

[0051] The preset setting interval is T0±⊿T, ⊿T=10%T0.

[0052] Optionally, before obtaining the real-time transport volume of the scraper conveyor, the method further includes:

[0053] Determine whether the scraper conveyor is turned on. If the scraper conveyor is in a stopped state, control the telescopic cylinder to fully retract. If the scraper conveyor is in an turned on state, control the scraper conveyor to enter an automatic tensioning mode.

[0054] Beneficial Effects

[0055] The automatic chain tensioning method provided in the embodiment of the present invention can accurately control the tension of the chain by obtaining the transport volume of the scraper conveyor in real time and calculating the chain preload and the theoretical pressure strength of the telescopic oil cylinder, avoiding problems such as accumulation, chain breakage or chain jamming due to the chain being too loose, and preventing excessive wear and damage to the equipment caused by the chain being too tight, thereby greatly improving the stability and reliability of the operation of the scraper conveyor. At the same time, the instantaneous tension of the chain is compared with the preload in real time, and the working state of the telescopic oil cylinder is adjusted according to the comparison result, ensuring that the chain is always in the best tension state, reducing the probability of equipment failure and extending the service life of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A flowchart of an automatic chain tensioning method according to an optional embodiment of the present application;

[0057] Figure 2 This is a schematic structural diagram of the tail of a scraper conveyor according to an optional embodiment of the present application;

[0058] Figure 3 This is a schematic structural diagram of a middle trough of a scraper conveyor according to an optional embodiment of the present application;

[0059] Figure 4 This is a schematic structural diagram of a tension detection module according to an optional embodiment of the present application.

[0060] The reference numerals are as follows:

[0061] 1. Telescopic cylinder; 2. Sprocket; 3. Telescopic frame; 4. Fixed trough; 5. Coal quantity scanner; 6. Tension detection module; 61. Wireless receiver; 62. Wireless collector; 63. Strain sensor. DETAILED DESCRIPTION

[0062] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" 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, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0063] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0064] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0066] See also Figures 1 to 4 As shown, according to an embodiment of the present application, there is provided an automatic chain tensioning method for a scraper conveyor, the scraper conveyor comprising a telescopic cylinder 1 and a tail, a middle trough and a head connected in sequence along the coal transportation direction, sprockets 2 are provided at the head and the tail, and the sprockets 2 are used for winding the chain.

[0067] Among them, the middle trough is the conveying trough body of the scraper conveyor, and the middle trough is used to provide a stable channel for materials such as coal.

[0068] Specifically, a drive motor is provided at the head of the machine, and an auxiliary motor is provided at the tail of the machine. The chain is installed inside the middle groove. Under the coordinated action of the drive motor and the auxiliary motor, the chain circulates along the middle groove, driving the scraper to transport coal and other materials from the tail of the machine to the head of the machine.

[0069] The sprocket 2 includes a driving sprocket and a driven sprocket, wherein the driving sprocket is installed at the head of the machine and the driven sprocket is installed at the tail of the machine. The driving sprocket and the driven sprocket mesh with the chain to transmit the power of the driving motor and the auxiliary motor to the chain to drive the scraper to move.

[0070] A telescopic oil cylinder 1 is also provided at the tail of the machine, and the telescopic oil cylinder 1 is used to adjust the position of the tail of the machine, thereby changing the tension of the chain.

[0071] Specifically, the tail includes a fixed trough body 4 and a telescopic frame body 3, the fixed trough body 4 and the telescopic frame body 3 overlap each other along the material transportation direction, the telescopic oil cylinder 1 is arranged on the fixed trough body 4, the fixed trough body 4 and the cylinder body of the telescopic oil cylinder 1 are relatively fixed, and the driving end of the telescopic oil cylinder 1 is connected to the telescopic frame body 3. In actual application, when the driving end of the telescopic oil cylinder 1 is extended, the telescopic frame body 3 is driven to move in a direction away from the fixed trough body 4, so that the tension force on the chain increases; when the driving end of the telescopic oil cylinder 1 is shortened, the telescopic frame body 3 is driven to move in a direction close to the fixed trough body 4, so that the tension force on the chain decreases.

[0072] Automatic chain tensioning methods include:

[0073] Step S1: Obtain the real-time transport volume of the scraper conveyor.

[0074] A coal quantity scanner 5 may be arranged above the middle trough, and the coal quantity scanner 5 can scan the amount of coal passing through the middle trough in real time, so as to accurately obtain the real-time transport volume of the scraper conveyor.

[0075] It is understandable that, due to the long laying length of the scraper conveyor, the coal mining machine walks on the scraper conveyor to cut coal. When the position of the coal mining machine is different, the amount of coal loaded on the scraper conveyor changes accordingly. It is difficult to scan the real-time coal loading on the entire scraper conveyor through a fixed point. This application adopts a multi-point laser scanning method to determine the real-time coal loading of the scraper conveyor, providing a basis for the automatic tensioning control of the chain. Specifically as follows: In actual application, there are several middle slots, and several coal quantity scanners 5 are also set. Several coal quantity scanners 5 are set one-to-one with several middle slots, and the distance between two adjacent coal quantity scanners 5 is the slot length of the middle slot.

[0076] The coal quantity scanner 5 may be a laser coal quantity scanner. The laser coal quantity scanner emits a laser beam and receives a signal reflected from the coal or other materials to calculate the distance L between the coal or other materials and the laser coal quantity scanner. i , when the distance H between the laser coal scanner and the middle plate of the scraper conveyor is known, the stacking height H of coal and other materials can be determined i =HL i , and finally calculate the real-time transport volume W of the scraper conveyor.

[0077] Specifically, the cross-section of materials such as coal can be divided into several small strips with a width of b, and the height H at the center of each small strip is accumulated. i , then multiply it by the width of the small strip to determine the area A of the horizontal end surface of the coal or other materials iIt is known that the total length of the scraper conveyor is L, the distance between two adjacent laser coal scanners is l, and the number of laser coal scanners is m = L / l. Then the total volume V of coal and other materials transported on the scraper conveyor conforms to the formula:

[0078]

[0079] The total weight Q of coal and other materials transported on the scraper conveyor conforms to the formula:

[0080]

[0081] The real-time transport volume W of the scraper conveyor conforms to the formula:

[0082] W=Q

[0083] Among them, A i Conforms to the formula:

[0084] A i =∑bH i =∑b(HL i )

[0085] Specifically, the real-time transport volume W of the scraper conveyor conforms to the formula:

[0086]

[0087] In the formula, ρ is the specific gravity of coal and other materials, which is 0.9t / m3; b is the width of the small strip, which is 0.01m; L is the total length of the scraper conveyor, which is 300m; l is the length of the middle trough, which is 1.75m; H is the distance between the laser coal scanner and the middle plate of the scraper conveyor, which is 2m; L i It is the distance between coal and other materials and the laser coal scanner, and its value is 1.3 to 1.7 m.

[0088] In this embodiment, after calculation in step S1, the real-time transport capacity of the scraper conveyor is W=2500t / h.

[0089] Step S2: Calculate the preload force of the chain and the theoretical pressure strength of the telescopic cylinder 1 based on the real-time transport volume.

[0090] Among them, in order to compensate for the elastic elongation of the chain after being pulled during operation, a preload force T0 can be applied to the chain through the telescopic cylinder 1 before the scraper conveyor is operated, and the chain produces an elastic elongation ΔL0 under the action of the preload force T0. If the elastic elongation of the chain under the normal load of the scraper conveyor is recorded as ΔL, then ΔL and ΔL0 have the following relationship: when ΔL<ΔL0, the chain maintains a certain preload force and will not relax, but the chain is too tight, which will increase the power consumption and wear of the scraper conveyor, and even cause accidents such as chain breakage; when ΔL=ΔL0, the preload force just eliminates the elastic elongation ΔL of the chain during normal operation, and the chain is appropriately tight; when ΔL>ΔL0, the chain will relax, affecting the normal operation of the conveyor, and in severe cases, the chain may even twist or break.

[0091] Specifically, the chain preload T0 complies with the formula:

[0092]

[0093] Among them, S1 is the theoretical tension of the chain at the winding point of the driven sprocket arranged at the tail of the machine, and the value of S1 is 2 to 3 kN.

[0094] Among them, S2 is the theoretical tension of the chain at the winding point of the driven sprocket set at the tail of the machine, and S2 conforms to the formula:

[0095]

[0096] In the formula, k r is the resistance coefficient of the chain passing through the driving sprocket and the driven sprocket, and its value is 0.045.

[0097] Among them, S3 is the theoretical tension of the chain at the winding point of the driving sprocket set at the head of the machine, and S3 conforms to the formula:

[0098] S3=S2-Lq0(μ * cosβ±sinβ)

[0099] Where, L is the laying length of the scraper conveyor, which is 300m; q0 is the weight of the chain per unit length, which is 1840N / m; β is the inclination angle of the working surface of the scraper conveyor, which is 0 degrees; μ * is the equivalent friction coefficient of the lower chain of the scraper conveyor.

[0100] Specifically, the equivalent friction coefficient μ of the lower chain of the scraper conveyor is * Conforms to the formula:

[0101]

[0102] It should be noted that when the lower chain of the scraper conveyor is sealed, μ* =0.3~0.4; When the lower chain of the scraper conveyor is not sealed, μ * =0.5~0.95.

[0103] Among them, S4 is the theoretical tension of the chain at the winding point of the driving sprocket set at the head of the machine, and S4 conforms to the formula:

[0104] S4=S1+Lq(μ * cosβ±sinβ)

[0105] In the formula, μ * is the equivalent friction coefficient of the upper chain of the scraper conveyor; q is the coal load per unit length of the scraper conveyor.

[0106] Specifically, the equivalent friction coefficient μ of the upper chain of the scraper conveyor is * Conforms to the formula:

[0107]

[0108] In the formula, V is the movement speed of the chain, which is 1.8 m / s; γ is the efficiency loss of the telescopic cylinder 1, which is 0.8; h is the coal loading height of the scraper conveyor;

[0109] The coal loading height h of the scraper conveyor conforms to the formula:

[0110]

[0111] Wherein, B is the width of the middle groove, which is 1m; h1 is the depth of the middle groove, which is 0.145m;

[0112] The coal load per unit length of the scraper conveyor q conforms to the formula:

[0113]

[0114] In the formula, g is the acceleration due to gravity, which is 9.80 m / s 2 ; V is the movement speed of the chain, which is 1.8m / s; W is the real-time transport capacity of the scraper conveyor, which is calculated by step S1 to be W=2500t / h.

[0115] It can be understood that T0=nF, n is the number of telescopic cylinders 1 at the tail of the aircraft, and F is the thrust of a single telescopic cylinder 1 .

[0116] Among them, the thrust F of a single telescopic cylinder 1 conforms to the formula:

[0117]

[0118] but because It is concluded that the theoretical pressure strength P of a single telescopic cylinder 1 conforms to the formula:

[0119]

[0120] Wherein, n is the number of telescopic cylinders 1 at the tail of the aircraft, which is 2; D is the inner diameter of the telescopic cylinder 1; γ is the efficiency loss of the telescopic cylinder 1, which is 0.8.

[0121] In this embodiment, after calculation in step S2, the theoretical pressure strength P of a single telescopic oil cylinder 1 is obtained to be 3 MPa.

[0122] Step S3: Control the movement of the telescopic cylinder 1 based on the theoretical pressure intensity.

[0123] It can be understood that controlling the movement of the telescopic cylinder 1 based on the theoretical pressure intensity can ensure that the chain tensioning force is in a theoretically ideal tensioning state.

[0124] Step S4: Detect the instantaneous tension of the chain.

[0125] Among them, the instantaneous tension of the chain conforms to the formula:

[0126]

[0127] In the formula, is the instantaneous tension of the chain; is the actual tension of the chain at the winding point of the driven sprocket; is the actual tension of the chain at the point where it is wound around the driven sprocket; is the actual tension of the chain at the winding point of the driving sprocket; It is the actual tension of the chain at the point where it is wound around the driving sprocket.

[0128] in, and All conform to the formula:

[0129] F=AEε

[0130] In the formula, F is tension, which is used to characterize and A is the cross-sectional area of ​​the chain. For chains with regular shapes, such as chains made of circular steel rings, the diameter of the steel rings can be measured and the area formula of a circle (S = πr 2 , where r is the radius) to calculate the cross-sectional area of ​​the chain; E is the elastic modulus of the chain, which is 210 GPa; ε is the strain value of the chain.

[0131] The scraper conveyor also includes a tension detection module 6, which is used to sense the strain values ​​at the winding-out point and winding-in point of the driven sprocket and the winding-out point and winding-in point of the driving sprocket, respectively, and then put them into the formula F=AEε to calculate, so as to obtain and And then determine the instantaneous tension of the chain in actual application

[0132] Specifically, the chain includes several steel rings, the tension detection module 6 includes at least two wireless receivers 61, several wireless collectors 62 and several strain sensors 63, at least two wireless receivers 61 are respectively arranged at the head and the tail, and several wireless collectors 62 and several strain sensors 63 are arranged one by one on several steel rings.

[0133] It is understandable that wiring grooves and sinking grooves can be processed on the steel ring. The wiring grooves are used for the arrangement of cables, and the sinking grooves are used for the installation of the wireless collector 62. The patch area is polished on the outer side of the straight section of the steel ring for installing the strain sensor 63. The wireless receiver 61 is installed at the head and tail of the scraper conveyor respectively. In actual applications, the strain generated by the force during the operation of the chain can be detected by the strain sensor 63, and the chain strain value ε is transmitted to the wireless collector 62 through the cable. After the wireless collector 62 obtains the data, it is sent to the wireless receiver 61 by wireless means. Since the wireless transmission method has a transmission distance limitation, the wireless receiver 61 can only collect the strain value ε of the chain at the head and tail.

[0134] Furthermore, in order to fully realize the solution proposed in this application, the scraper conveyor also includes a data analysis control module. The wireless receiver 61 transmits data to the data analysis control module via Ethernet, and the data analysis control module is used to analyze and process the data.

[0135] Step S5: compare the instantaneous tension and the preload force in real time, and adjust the working state of the telescopic cylinder 1 based on the comparison result.

[0136] Among them, the instantaneous tension and the preload are compared in real time, and the working state of the telescopic cylinder 1 is adjusted based on the comparison result, including: comparing the instantaneous tension and the preset setting interval in real time; when the instantaneous tension is in the preset setting interval, keeping the extension amount of the telescopic cylinder unchanged; when the instantaneous tension is greater than the upper limit value of the preset setting interval, controlling the extension amount of the telescopic cylinder 1 to decrease; when the instantaneous tension is less than the lower limit value of the preset setting interval, controlling the extension amount of the telescopic cylinder 1 to increase.

[0137] Specifically, the instant tension within the preset setting interval is used to indicate that the chain is in an ideal tension state, maintaining the pressure of the telescopic cylinder 1 unchanged, and the telescopic cylinder 1 stops moving; the instant tension greater than the upper limit of the preset setting interval is used to indicate that the chain is too tight, reducing the pressure of the telescopic cylinder 1, controlling the retraction cylinder to retract the cylinder stroke, and reducing the extension amount; the instant tension less than the lower limit of the preset setting interval is used to indicate that the chain is too loose, increasing the pressure of the telescopic cylinder 1, controlling the retraction cylinder to increase the cylinder stroke, and increasing the extension amount.

[0138] The preset setting interval is T0±⊿T, ⊿T=10%T0.

[0139] Specifically, if It indicates that the chain is in an ideal tension state, the pressure of telescopic cylinder 1 is maintained unchanged, and telescopic cylinder 1 stops moving; if It indicates that the chain is too tight, reduce the pressure of telescopic cylinder 1, control the retracting cylinder to shrink the cylinder stroke, and reduce the extension amount; if This indicates that the chain is too loose. Increase the pressure of telescopic cylinder 1, control the retracting cylinder to increase the cylinder stroke and increase the extension amount.

[0140] It should be noted that when the scraper conveyor also includes a data analysis control module, the data analysis control module can pre-store the calculation formulas and control logic of step S1, step S2, step S3, step S4 and step S5, so as to achieve the automatic tensioning function of the chain.

[0141] Specifically, in this embodiment, first, the real-time transportation volume of the scraper conveyor is calculated using a laser coal volume scanner, and the obtained data is transmitted to the data analysis control module. Next, the data analysis control module calculates the theoretical pressure strength of the telescopic cylinder 1 and the preload of the chain based on the real-time transportation volume of the scraper conveyor, and at the same time transmits the theoretical pressure strength control signal of the telescopic cylinder 1 to the telescopic cylinder 1, prompting it to perform the telescopic action. Afterwards, the tension detection module 6 measures the actual tension of the chain at the head and tail of the machine, and transmits the data to the data analysis control module, which calculates the instantaneous tension of the chain. Finally, the data analysis control module compares the instantaneous tension with the preload, and controls the movement of the telescopic cylinder 1 accordingly.

[0142] It is understandable that in or In the case of changing the extension amount of telescopic cylinder 1, repeat steps S4 and S5 until The telescopic cylinder 1 stops moving and the chain is in an ideal tension state.

[0143] In this application, by obtaining the transport volume of the scraper conveyor in real time and calculating the chain preload and the theoretical pressure strength of the telescopic cylinder 1, the tension of the chain can be accurately controlled to avoid problems such as accumulation, chain breakage or chain jamming due to the chain being too loose, and to prevent excessive wear and damage to the equipment caused by the chain being too tight, greatly improving the stability and reliability of the scraper conveyor operation. At the same time, the chain instant tension and preload are compared in real time, and the working state of the telescopic cylinder 1 is adjusted according to the comparison results to ensure that the chain is always in the best tension state, reducing the probability of equipment failure and extending the service life of the equipment.

[0144] Furthermore, the automatic chain tensioning method provided by the present application can quickly respond to changes in the transport volume of the scraper conveyor, timely adjust the chain tension, and ensure that the equipment can operate efficiently under different workloads, thereby improving the production efficiency of the entire coal transportation system. At the same time, there is no need for frequent manual intervention to adjust the chain tension, which saves labor costs and time costs and improves the operating efficiency of the equipment.

[0145] In some possible embodiments disclosed in the present application, before obtaining the real-time transport volume of the scraper conveyor, the method further includes:

[0146] Determine whether the scraper conveyor is turned on. If the scraper conveyor is in the stopped state, the telescopic cylinder 1 is controlled to be fully retracted. If the scraper conveyor is in the turned on state, the scraper conveyor is controlled to enter the automatic tensioning mode.

[0147] When the scraper conveyor is in a stopped state, the telescopic oil cylinder 1 is controlled to be fully retracted, which can avoid the oil cylinder from being continuously subjected to pressure under unnecessary circumstances, reduce the fatigue loss of the oil cylinder, and extend its service life. At the same time, it also helps to reduce the energy consumption of the equipment in the stopped state and achieve the purpose of energy saving.

[0148] When the scraper conveyor is in the on state, the automatic tensioning mode is controlled to ensure that the chain always maintains the appropriate tension during the operation of the equipment. This can effectively prevent problems such as coal accumulation, chain breakage or chain jamming caused by chain slack, and improve the operating efficiency and stability of the equipment.

[0149] Specifically, when it is necessary to determine whether the scraper conveyor is turned on, the data analysis control module will receive the operating status signal from the scraper conveyor. This signal can be obtained by connecting to the control system of the scraper conveyor or installing a specific sensor. If the data analysis control module determines that the scraper conveyor is in a stopped state, it will immediately issue a control instruction to fully retract the telescopic cylinder 1. When the data analysis control module determines that the scraper conveyor is in the turned-on state, it will start the automatic tensioning mode. In this mode, the data analysis control module first calculates the preload force of the chain and the theoretical pressure strength of the telescopic cylinder 1 according to the pre-stored calculation formula and control logic, using the real-time transportation volume and other data of the scraper conveyor obtained from the laser coal volume scanner and other equipment. Then, the data analysis control module transmits the theoretical pressure strength control signal to the telescopic cylinder 1, controls the telescopic cylinder 1 to move to a suitable position, so as to achieve the tensioning of the chain. Then, the tension detection module 6 measures the instantaneous tension of the chain and transmits the data back to the data analysis control module. The data analysis control module compares the instantaneous tension and the preload in real time, and continuously adjusts the working state of the telescopic cylinder 1 according to the comparison result to ensure that the chain always maintains an ideal tension level to meet the normal operation requirements of the scraper conveyor.

[0150] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0151] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A chain automatic tensioning method for a scraper conveyor, the scraper conveyor comprising a telescopic oil cylinder (1) and a tail, a middle trough and a head connected in sequence along the coal transportation direction, the head and the tail being provided with a sprocket (2), the sprocket (2) being used for winding a chain, characterized in that: The method comprises: Obtaining the real-time transport volume of the scraper conveyor; Calculating the preload force of the chain and the theoretical pressure strength of the telescopic cylinder (1) based on the real-time transport volume; Controlling the movement of the telescopic cylinder (1) based on the theoretical pressure intensity; detecting instantaneous tension of the chain; The instantaneous tension and the pre-tightening force are compared in real time, and the working state of the telescopic oil cylinder (1) is adjusted based on the comparison result.

2. The automatic chain tensioning method according to claim 1, characterized in that: The preload force of the chain complies with the formula: In the formula, T0 is the preload force of the chain; S1 is the theoretical tension of the chain at the winding-out point of the sprocket (2) arranged at the tail of the machine; S2 is the theoretical tension of the chain at the winding-in point of the sprocket (2) arranged at the tail of the machine; S3 is the theoretical tension of the chain at the winding-out point of the sprocket (2) arranged at the head of the machine; and S4 is the theoretical tension of the chain at the winding-in point of the sprocket (2) arranged at the head of the machine.

3. The automatic chain tensioning method according to claim 2, characterized in that: The value range of S1 is 2 to 3 kN; S2 complies with the formula: In the formula, k r is the resistance coefficient of the chain passing around the sprocket (2); S3 complies with the formula: <h2 style=";text-align:left;direction:ltr">S3 = S2 - Lq0(μ)<h2 style=";text-align:left;direction:ltr"> * <h2 style=";text-align:left;direction:ltr"> cosβ±sinβ) Wherein, L is the laying length of the scraper conveyor; q0 is the weight per unit length of the chain; μ * is the equivalent friction coefficient of the lower chain of the scraper conveyor; β is the inclination angle of the working surface of the scraper conveyor; S4 complies with the formula: S4=S1+Lq(μ * cosβ±sinβ) Where, q is the coal load per unit length of the scraper conveyor; μ * is the equivalent friction coefficient of the upper chain of the scraper conveyor.

4. The automatic chain tensioning method according to claim 3, characterized in that: The equivalent friction coefficient μ of the lower chain of the scraper conveyor * Conforms to the formula: The equivalent friction coefficient μ of the upper chain of the scraper conveyor * Conforms to the formula: In the formula, V is the movement speed of the chain; γ is the efficiency loss of the telescopic cylinder (1); h is the coal loading height of the scraper conveyor; The coal loading height h of the scraper conveyor complies with the formula: Wherein, B is the width of the middle groove; h1 is the depth of the middle groove; The coal load per unit length q of the scraper conveyor conforms to the formula: Wherein, W is the real-time transport volume of the scraper conveyor; g is the acceleration of gravity.

5. The automatic chain tensioning method according to claim 1, characterized in that: The middle troughs are provided in a plurality, and a coal quantity scanner (5) is provided at each of the middle troughs in a one-to-one correspondence, and the coal quantity scanner (5) is used to obtain the real-time transport volume of the scraper conveyor; The distance between two adjacent coal quantity scanners (5) is the slot length of the middle slot.

6. The automatic chain tensioning method according to claim 2, characterized in that: The theoretical pressure strength of the telescopic oil cylinder (1) complies with the formula: In the formula, n is the number of the telescopic cylinders (1); D is the inner diameter of the telescopic cylinder (1); and γ is the efficiency loss of the telescopic cylinder (1).

7. The automatic chain tensioning method according to claim 1, characterized in that: The instantaneous tension of the chain complies with the formula: In the formula, is the instantaneous tension of the chain; is the actual tension of the chain at the winding-out point of the sprocket (2) arranged at the tail of the machine; is the actual tension of the chain at the winding point of the sprocket (2) arranged at the tail of the machine; is the actual tension of the chain at the winding-out point of the sprocket (2) arranged at the machine head; is the actual tension of the chain at the winding point of the sprocket (2) arranged at the machine head; in, and All conform to the formula: F=AEε Wherein, F is tension; A is the cross-sectional area of ​​the chain; E is the elastic modulus of the chain; ε is the strain value of the chain.

8. The automatic chain tensioning method according to claim 7, characterized in that: The scraper conveyor further comprises a tension detection module (6), wherein the tension detection module (6) is used to sense strain values ​​at the positions of the winding-out point and the winding-in point of the sprocket (2) arranged at the tail of the machine and the winding-out point and the winding-in point of the sprocket (2) arranged at the head of the machine; The chain comprises a plurality of steel rings, the tension detection module (6) comprises at least two wireless receivers (61), a plurality of wireless collectors (62) and a plurality of strain sensors (63), at least two of the wireless receivers (61) are respectively arranged at the head and the tail, and the plurality of wireless collectors (62) and the plurality of strain sensors (63) are arranged on the plurality of steel rings in a one-to-one correspondence.

9. The automatic chain tensioning method according to claim 2, characterized in that: The real-time comparison of the instantaneous tension and the preload force, and adjusting the working state of the telescopic cylinder (1) based on the comparison result, comprises: Comparing the instantaneous tension with a preset setting interval in real time; When the instantaneous tension is within the preset setting interval, the extension amount of the telescopic cylinder is kept unchanged; when the instantaneous tension is greater than the upper limit value of the preset setting interval, the extension amount of the telescopic oil cylinder (1) is controlled to decrease; when the instantaneous tension is less than the lower limit value of the preset setting interval, the extension amount of the telescopic oil cylinder (1) is controlled to increase. The preset setting interval is T0±⊿T, ⊿T=10%T0.

10. The automatic chain tensioning method according to claim 9, characterized in that: Before obtaining the real-time transport volume of the scraper conveyor, the method further includes: It is determined whether the scraper conveyor is turned on. If the scraper conveyor is in a stopped state, the telescopic cylinder (1) is controlled to be fully retracted. If the scraper conveyor is in an turned on state, the scraper conveyor is controlled to enter an automatic tensioning mode.

Images