Method for regulating a belt conveyor tensioner based on destructive counter-tension

Abstract

The application provides a belt conveyor tensioning device regulation method based on destructive counter-tension, and twice regulation is arranged, the twice regulation of the application is correlated, the maximum T actual tension setting in t time is achieved through force offset and simultaneous action of sufficient time, the destructive counter-tension is eliminated; and the T actual tension remains unchanged in t, and the occurrence of the destructive counter-tension is often an unexpected situation, the occurrence of the destructive counter-tension is short-time or instantaneous, the destructive counter-tension can be eliminated through t control, so that the t is set as the maximum in the first regulation. Otherwise, the second regulation is arranged.

Description

Technical Field

[0001] This invention relates to the field of intelligent control technology for belt conveyors, and in particular to a method for regulating the tensioning device of a belt conveyor based on destructive counter-tension. Background Technology

[0002] The viscoelasticity of belt conveyors is fundamentally caused by the conveyor belt itself, which serves as both its drag and load-bearing component. Conveyor belts are essentially composed of a tensile core and a rubber layer covering it. The tensile core is currently made of various materials such as cotton canvas, nylon canvas, polyester canvas, and steel cord. As can be seen from the composition of the conveyor belt and its function in a belt conveyor, the conveyor belt is tensioned during normal use, meaning it is stretched longitudinally. The device that completes the conveyor belt tensioning process is the belt conveyor tensioning system. The pretension it generates prevents the conveyor belt from slipping on the drive drum and simultaneously controls the sag of the belt between the two sets of idlers to be less than a certain value, thereby reducing conveying resistance.

[0003] However, when a belt conveyor malfunctions and stops in an emergency, especially under heavy load conditions, the slack side tension will increase in a very short time, even reaching 3 to 5 times the normal tension value. This tension is called destructive counter-tension. If the tensioning system cannot respond quickly, the belt conveyor or tensioning device designed and selected according to the rated parameters will be damaged. In severe cases, it may even cause the wire rope to break, resulting in a serious accident where the tensioning trolley derails and flies off, injuring people. Summary of the Invention

[0004] In view of the above-mentioned shortcomings, the present invention proposes a method for adjusting the tensioning device of a belt conveyor based on destructive counter-tension, comprising the following steps: The tension on the wire rope is measured by a detection device and recorded as T. 实时 ; The real-time tension force output by the tensioning device to the tensioning carriage is denoted as T. 实拉 When there is no destructive counter-tension during normal operation, T 实时 =T 实拉 / 2N, where N is the number of movable pulleys connected to the tensioning carriage and the tensioning device; A destructive counter-tension, denoted as T, occurs on the tensioning trolley of the belt conveyor. 破反 ; When the detection device detects the tension T on the wire rope 实时 >1.5(T 实拉 / 2N), indicating the appearance of destructive counter-tension, initiating tension and stroke control; the control is subject to two constraints, the first being tension limitation; the setting is based on the destructive counter-tension T 破反 and the tension output force T of the tensioning device 实拉 The resultant force forms the acceleration 'a' that tightens the trolley; secondly, there is the travel limit, which is derived from formulas one and two to form formula three: Formula 1; Formula 2; It can be concluded that: Formula 3; In the above formula, m 绞车 Let 'a' be the mass of the tensioning trolley, and 'a' be the acceleration; let L be the total stroke of the tensioning trolley. 车总 The maximum position of the belt conveyor after tensioning during operation is denoted as L. 车现 The reserved reaction follow-up stroke when a destructive counter-tension occurs is L. 车总 -L 车现 , denoted as L 跟随 t represents the control time; When the detection shows T 破反 At that time, control T 实拉 Within time t, take ≤2T n Adjustments (following T) 破反 The value of T is used to minimize the acceleration a of the tension trolley, even if the tension fluctuation is small enough. 破反 ≤2T n According to Formula 3, the value of t is infinitely large, eventually making T... 破反 eliminate.

[0005] T n The tension required for the belt conveyor under rated operating conditions remains constant during normal use; 2T n This is the maximum tension that the tensioning device can output without being damaged.

[0006] If T 破反 >2T n Take T 实拉 =2T n To regulate, according to Formula 3, the value of t changes with T. 破反 The force decreases as the resistance increases. If the destructive reaction force is not eliminated after time t, the wire rope is released, causing the tensioning trolley to move in the direction of the destructive reaction force, with a moving distance of L. 跟随 . Attached Figure Description

[0007] Figure 1 This is a schematic diagram of the control method of this device.

[0008] Figure 2 , 3 This is a schematic diagram of the two states.

[0009] In the diagram: tensioning device 10, tensioning trolley 20, movable pulley 21, detection device 30. Detailed Implementation

[0010] See Figure 1-3 The present invention provides a method for controlling the tensioning device of a belt conveyor based on destructive counter-tension, comprising the following steps: The tension on the wire rope is detected by the detection device 30 and recorded as T. 实时 ; The real-time output tension force of the tensioning device 10 to the tensioning carriage 20 is denoted as T. 实拉 When there is no destructive counter-tension during normal operation, T 实时 =T 实拉 / 2N, where N is the number of movable pulleys 21 connected between the tensioning carriage 20 and the tensioning device 30; in one embodiment, the fixed pulleys are the three on the left side connected to the tensioning carriage, then N is 3; A destructive counter-tension, denoted as T, occurs on the tensioning trolley of the belt conveyor. 破反 ; When the detection device detects the tension T on the wire rope 实时 >1.5(T 实拉 / 2N), indicating the appearance of destructive counter-tension, initiates tension and stroke control to address the destructive counter-tension and prevent damage to the belt conveyor or derailment / runaway accidents of the tensioning trolley. Two control limitations exist: first, a tension limit, meaning the tension force is adjusted within the power range of the tensioning device; second, the destructive counter-tension T is set... 破反 and the tension output force T of the tensioning device 实拉 The resultant force of the two forces forms the acceleration 'a' of the tensioning trolley; the second is the stroke limit, i.e., the adjustment time, which means adjusting the movement of the tensioning trolley within the mechanical strength and stroke range of the belt conveyor. Formula 3 is obtained from Formula 1 and Formula 2: Formula 1; Formula 2; It can be concluded that: Formula 3; In the above formula, m 绞车 Let 'a' be the mass of the tensioning trolley, and 'a' be the acceleration; let L be the total stroke of the tensioning trolley. 车总 The maximum position of the belt conveyor after tensioning during operation is denoted as L. 车现 The reserved reaction follow-up stroke when a destructive counter-tension occurs is L. 车总 -L 车现 , denoted as L 跟随 t represents the control time; When the detection shows T 破反 At that time, control T 实拉 Within time t, take ≤2Tn Adjustments (following T) 破反 The value of T is used to minimize the acceleration a of the tension trolley, even if the tension fluctuation is small enough. 破反 ≤2T n According to Formula 3, the value of t is infinitely large, eventually making T... 破反 Eliminate tensioning device, activate brake to stop machine, and achieve control purpose.

[0011] If T 破反 >2T n According to Formula 3, the value of t changes with T. 破反 The destructive counter-tension decreases as the tension increases, while the initial instantaneous value of the destructive counter-tension is the largest, subsequently decreasing. If the destructive counter-tension is not eliminated after time t (the maximum executable value calculated based on the maximum counter-tension), then the wire rope is released, causing the tensioning trolley to move in the direction of the destructive counter-tension, with a moving distance of L. 跟随 When the distance traveled reaches L 跟随 The tensioning device activates the brake to stop the machine, and at the same time, the stop block at the front of the tensioning trolley also prevents the movement of the tensioning device, thus achieving the control purpose.

[0012] When destructive counter-tension occurs, this patent first sets the tension force to its maximum, maximizing its ability to counteract the counter-tension. Simultaneously, t also reaches its maximum value, providing a buffer time for the counter-tension. This measure is tension control, serving as a primary control measure, and within the maximum time, through the maximum T... 实拉 To reduce the acceleration of the tensioning carriage caused by the destructive reaction force, if the reaction force is eliminated, secondary control is not initiated. If it is not eliminated, then force a still exists, and the tensioning carriage tends to move in the direction of the destructive reaction tension. At this time, secondary control is initiated, stroke is limited, and the relaxation of the wire rope is controlled by L. 跟随 The travel distance is set to eliminate the reaction force.

[0013] The two regulation processes in this invention are interrelated, and the maximum T within time t is... 实拉 The setting is that the reaction force is eliminated through the simultaneous action of force cancellation and sufficient time; and within t, T 实拉 The system remains unchanged, while the occurrence of disruptive forces often occurs unexpectedly. These forces are short-lived or instantaneous, and can be eliminated by controlling t. Therefore, in the first adjustment, t is set to its maximum. Otherwise, a second adjustment is set.

[0014] This solution differs from the original design, which employed a single control measure when a failure occurred, such as simply increasing the tensile force (T). 实拉 3-5 times T n This kind of force control applied excessive force to the tensioning trolley instantly, and the T... 实拉Opposite to the direction of the breaking reaction force, it will exert a large instantaneous force on the wire rope or other mechanical structure, causing mechanical damage to the components. Another control method is to reserve L for the tensioning trolley. 跟随 During the swimming stroke, the instantaneous appearance of the reaction force causes the tensioning trolley to have a large instantaneous acceleration, although L is reserved. 跟随 However, this method is prone to derailment and runaway accidents due to large acceleration. It is evident that the two control methods mentioned above are not internally related; the control of the tension is not fundamentally related to time or the release of the wire rope, resulting in poor control effectiveness.

[0015] The embodiments of this solution have been described in detail above with reference to the accompanying drawings. However, this solution is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of this patent.

Claims

1. A method for controlling the tensioning device of a belt conveyor based on destructive counter-tension, characterized in that... Includes the following steps: The tension on the wire rope is measured by a detection device and recorded as T. 实时 ; The real-time tension force output by the tensioning device to the tensioning carriage is denoted as T. 实拉 When there is no destructive counter-tension during normal operation, T 实时 =T 实拉 / 2N, where N is the number of movable pulleys connected to the tensioning carriage and the tensioning device; A destructive counter-tension, denoted as T, occurs on the tensioning trolley of the belt conveyor. 破反 ; When the detection device detects the tension T on the wire rope 实时 >1.5(T 实拉 / 2N), indicating the appearance of destructive counter-tension, and the start of tension and stroke regulation; There are two control and restriction conditions; the first is the tension limit. Set by destructive counter-tension T 破反 and the tension output force T of the tensioning device 实拉 The resultant force forms the acceleration 'a' that tightens the trolley; secondly, there is the travel limitation, which is derived from formulas one and two to form formula three: T 破反 -T 实拉 =m 绞车 a------------Formula 1; 2L 跟随 =at 2 Formula 2; It can be concluded that: In the above formula, m 绞车 Let 'a' be the mass of the tensioning trolley, and 'a' be the acceleration. The total travel distance of the tensioning trolley is denoted as L. 车总 The maximum position of the belt conveyor after tensioning during operation is denoted as L. 车现 The reserved reaction follow-up stroke when a destructive counter-tension occurs is L. 车总 -L 车现 , denoted as L 跟随 t represents the control time; When the detection shows T 破反 At that time, control T 实拉 Take the maximum value 2T n To regulate and control Make t reach its maximum value, and make T 破反 Eliminate within t to achieve the control objective; If T is detected 破反 It still exists, and after time t, the tensioning device T remains. 实拉 Keeping the wire rope unchanged, control the release of the tensioning trolley to move in the direction of the destructive counter-tension, and move a distance of L. 跟随 .

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