Adjustable tensioning device for large belt conveying

Abstract

The utility model discloses an adjustable tensioning device for large belt conveying, which relates to the field of belt transmission tensioning and comprises a fixed frame and a sliding frame, the sliding frame is slidably mounted on the fixed frame, a driven belt pulley is rotatably arranged on the sliding frame, and the sliding frame moves along the height direction of the fixed frame. The sliding frame is arranged on the driving belt wheel and used for adjusting the distance between the driven belt wheel and the driving belt wheel, a weight box is arranged at the bottom of the sliding frame, the tensioning degree of the belt is adjusted by placing different numbers of weight balls into the weight box, and through the combined design of the weight box and the weight balls, refined and stepped adjustment of the tensioning force of the belt is achieved. On one hand, the number of the counterweight balls can be increased or decreased one by one, an operator can flexibly control the number of the counterweight balls placed in the counterweight box according to the actual tension requirement of the belt, the counterweight blocks with fixed weight do not need to be forcibly increased or decreased, and the problem of'interference 'or'insufficient' of tension force is effectively avoided.

Description

Technical Field

[0001] This utility model relates to the field of belt drive tensioning technology, specifically an adjustable tensioning device for large belt conveyors. Background Technology

[0002] In industrial production, large belt conveyors, as key continuous conveying equipment, undertake the long-distance, high-load transfer of large quantities of bulk materials (such as ore, coal, and sand). Their operational stability directly determines the efficiency and safety of the entire production process. As a core component of large belt conveyors, the performance of the belt tensioning device directly affects the belt's transmission efficiency, service life, and the reliability of equipment operation. Therefore, extremely high requirements are placed on the functionality and practicality of the tensioning device.

[0003] Currently, tensioning devices used in large belt conveyors are mainly divided into two categories: power-driven and counterweight-driven. Power-driven devices, primarily driven by cylinders, are used in some scenarios where timely adjustment is crucial due to their fast response. However, cylinder-driven tensioning devices have a core, unavoidable drawback: to meet the tension requirements of large belt conveyors, the cylinders must withstand high pressure conditions for extended periods. Key components such as the cylinder body and seals are prone to wear and aging under continuous high pressure, significantly shortening the equipment's lifespan. Typically, they can only maintain stable operation for 1-2 years. Subsequent repairs and replacements not only increase equipment maintenance costs but also disrupt production continuity due to downtime. More importantly, if the cylinder malfunctions, such as leaks or piston rod jamming, the driven pulley will lose driving force, instantly disrupting the belt's original tension balance. This can lead to belt slippage and material conveying interruptions, or even excessive belt slack causing misalignment, folding, or friction and collision with other conveyor components, resulting in equipment failure and even safety accidents, causing significant economic losses to enterprises.

[0004] Compared to cylinder-driven tensioning devices, counterweight tensioning devices rely on gravity to achieve stable tension output without requiring additional power, offering a significant advantage in tension stability and thus being more widely used in large belt conveyor systems. However, most mainstream counterweight tensioning devices currently use cement plates as the counterweight carrier. This method also reveals serious performance shortcomings in practical applications: Firstly, the weight specifications of the cement plates are usually fixed standard weights such as 50kg and 100kg, resulting in a large range of counterweights that cannot be finely adjusted according to the actual tension requirements of the belt. For example, when the belt becomes slightly loose due to wear or temperature changes, and only adding 5-10kg of counterweight is needed to restore the appropriate tension, the lack of a corresponding weight of cement plate forces the addition of a 50kg counterweight cement plate, leading to excessive belt tension, accelerated wear on the belt and pulleys, and shortened belt life. Conversely, when the belt tension is too high and a slight reduction in weight is needed, the inability to disassemble the counterweight cement plates means that one piece must be removed entirely, causing a sudden drop in tension and increasing the risk of belt slippage.

[0005] On the other hand, the integral structure of the counterweight cement plate renders the tensioning device completely incapable of correcting belt misalignment. During the operation of large belt conveyors, belt misalignment is extremely common due to factors such as uneven material distribution, belt manufacturing errors, and frame installation deviations. With tensioning devices using counterweight cement plates, the center of gravity of the counterweight is always fixed directly below the sliding frame, making it impossible to adjust the force balance of the sliding frame by adjusting the counterweight distribution, and thus impossible to correct belt misalignment. Utility Model Content

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an adjustable tensioning device for large belt conveyors to solve the problem of uncontrollable belt tension.

[0007] The purpose of this utility model is achieved through the following technical solution: an adjustable tensioning device for large belt conveyors, comprising a fixed frame and a sliding frame, wherein the sliding frame is slidably mounted on the fixed frame, a driven pulley is rotatably mounted on the sliding frame, and the sliding frame moves along the height direction of the fixed frame to adjust the distance between the driven pulley and the driving pulley. A counterweight box is provided at the bottom of the sliding frame, and the tension of the belt is adjusted by placing different numbers of counterweight balls into the counterweight box.

[0008] Furthermore, the fixed frame includes two parallel square tubes, which are vertically fixedly installed. The sliding frame includes an upper crossbeam, a lower crossbeam, and two U-shaped plates. The two ends of the upper crossbeam are respectively fixedly connected to one end of the two U-shaped plates, and the two ends of the lower crossbeam are respectively fixedly connected to the other end of the two U-shaped plates. The square tubes are slidably adapted to fit within the U-shaped opening of the U-shaped plates. Bearing seats are fixed to the side walls of the U-shaped plates, and the two ends of the driven pulley are respectively rotatably mounted on the two bearing seats.

[0009] Furthermore, both sides of the counterweight box in the width direction are fixed with screws, the screws are located in the middle of the side wall of the counterweight box, and the lower crossbeam has a through hole corresponding to the position of the screw. The end of the screw away from the counterweight box passes through the through hole and is threaded to a limit nut. The diameter of the limit nut is larger than the diameter of the through hole.

[0010] Furthermore, a partition is fixed inside the counterweight box, which divides the counterweight box into a left chamber and a right chamber along its length. The belt can be corrected by adjusting the weight difference between the left and right chambers.

[0011] Furthermore, the square tube and the U-shaped plate are in a clearance fit.

[0012] Furthermore, the clearance between the square tube and the U-shaped plate is 1mm-5mm.

[0013] Furthermore, a grid-like component is provided in both the left and right chambers. The grid-like component includes multiple horizontal plates and multiple vertical plates. The vertical plates are fixedly passed through the horizontal plates. The multiple horizontal plates and multiple vertical plates are connected to form a grid-like cavity. Each cavity can only hold one counterweight ball on the horizontal plane.

[0014] Furthermore, a connecting rod is fixed to the counterweight ball, and the connecting rod is T-shaped.

[0015] The beneficial effects of this utility model are:

[0016] 1. Through the combination design of "counterweight box + counterweight ball", the belt tension can be adjusted in a precise and step-by-step manner. On the one hand, the counterweight ball can be added or removed individually. The operator can flexibly control the number of counterweight balls put into the counterweight box according to the actual tension requirements of the belt, without having to add or remove counterweight blocks of fixed weight, effectively avoiding the problem of "excessive" or "insufficient" tension.

[0017] 2. A partition is installed inside the counterweight box, dividing it into a left and right chamber. Belt alignment can be achieved by adjusting the difference in counterweight between the two chambers. When the belt deviates due to uneven material distribution, manufacturing errors, or frame deviations, operators do not need to rely on external alignment rollers or adjusting idlers. They only need to increase the number of counterweight balls in the chamber on the deviating side. By shifting the center of gravity of the counterweight, the force balance of the sliding frame is changed, causing a slight deviation of the driven pulley, thereby accurately correcting the belt's running trajectory. This design not only eliminates the purchase and installation costs of independent alignment equipment and simplifies the overall structure of large belt conveyors, but also reduces maintenance steps. It eliminates the need to maintain both the tensioning and alignment devices simultaneously, reducing the workload and operational difficulty for maintenance personnel and significantly improving the economy and convenience of equipment operation. Attached Figure Description

[0018] Figure 1 This is a three-dimensional schematic diagram of an adjustable tensioning device for large belt conveyors according to the present invention. Figure 1 ;

[0019] Figure 2 This is a schematic diagram of the counterweight ball in an adjustable tensioning device for large belt conveyors according to this utility model.

[0020] Figure 3 This is a three-dimensional schematic diagram of an adjustable tensioning device for large belt conveyors according to the present invention. Figure 2 ;

[0021] Figure 4 This is a schematic diagram of the mesh-type component in an adjustable tensioning device for large belt conveyors according to the present invention.

[0022] In the diagram, 1-fixed frame, 2-sliding frame, 3-driven pulley, 4-counterweight box, 5-upper crossbeam, 6-lower crossbeam, 7-U-shaped plate, 8-counterweight ball, 9-screw, 10-through hole, 11-limiting nut, 12-partition, 13-left chamber, 14-right chamber, 15-horizontal plate, 16-vertical plate, 17-connecting rod, 18-bearing seat. Detailed Implementation

[0023] Example 1

[0024] like Figures 1 to 4As shown, an adjustable tensioning device for large belt conveyors includes a fixed frame 1 and a sliding frame 2. The sliding frame 2 is slidably mounted on the fixed frame 1. A driven pulley 3 is rotatably mounted on the sliding frame 2. The sliding frame 2 moves along the height direction of the fixed frame 1 to adjust the distance between the driven pulley 3 and the driving pulley. A counterweight box 4 is provided at the bottom of the sliding frame 2. The tension of the belt is adjusted by placing different numbers of counterweight balls 8 into the counterweight box 4. The driven pulley is connected to the driving pulley via belt drive to form a belt conveyor structure. Since the position of the driving pulley is fixed, the tension can only be adjusted by adjusting the position of the driven pulley 3. Belt tensioning is achieved by placing different numbers of counterweight balls 8 into the counterweight box 4, which apply different forces to the sliding frame 2, thus keeping the belt in a tensioned state. Compared with cylinder-driven tensioning devices, this device relies on the gravity of the counterweight balls 8 to achieve tension output, eliminating the need for high-pressure power equipment such as cylinders. This fundamentally avoids problems such as cylinder wear and seal aging caused by long-term high pressure on cylinders. It saves the cost of regular cylinder maintenance and replacement, and also eliminates the risks of tension imbalance and belt failure due to cylinder failure, significantly improving the reliability and safety of the device and reducing production interruptions caused by equipment failure. Compared with the disadvantages of traditional counterweight cement slabs with "fixed weight and large span" adjustment, this device achieves refined and step-by-step adjustment of belt tension through the combination design of "counterweight box 4 + counterweight balls 8". On the one hand, the counterweight balls 8 can be added or removed individually. Operators can flexibly control the number of counterweight balls 8 placed in the counterweight box 4 according to the actual tension requirements of the belt (such as slight slack or over-tightness due to wear or temperature changes). There is no need to add or remove counterweight blocks of fixed weight, which effectively avoids the problem of "excessive" or "insufficient" tension. It prevents the belt from aggravating friction and wear between the belt and the pulley due to excessive tension, and also prevents the belt from slipping due to insufficient tension. This significantly extends the service life of the belt and ensures the continuity of material conveying.

[0025] Example 2

[0026] Based on Example 1, such as Figure 1 and Figure 2 As shown, a connecting rod 17 is fixed on the counterweight ball 8. The connecting rod 17 is T-shaped. The T-shaped connecting rod design not only makes it easy to grasp, but also prevents the counterweight ball from slipping during the picking and putting process, effectively avoiding the risk of falling and injuring people when transporting traditional counterweight blocks, and improving the safety of the operation process.

[0027] Example 3

[0028] Based on Example 2, such as Figure 1 and Figure 3As shown, the fixed frame 1 includes two parallel square tubes, which are vertically fixed. The sliding frame 2 includes an upper crossbeam 5, a lower crossbeam 6, and two U-shaped plates 7. The two ends of the upper crossbeam 5 are respectively fixedly connected to one end of the two U-shaped plates 7, and the two ends of the lower crossbeam 6 are respectively fixedly connected to the other end of the two U-shaped plates 7. The square tubes slide and fit into the U-shaped openings of the U-shaped plates 7. Bearing seats 18 are fixed to the side walls of the U-shaped plates 7. The two ends of the driven pulley 3 are respectively rotatably mounted on the two bearing seats 18. Through the cooperation between the U-shaped plates 7 and the square tubes, the sliding frame 2 can move along the height direction of the fixed frame 1, which facilitates the installation of the belt and ensures that the belt is in a tensioned state after installation.

[0029] Example 4

[0030] Based on Example 3, such as Figure 1 and Figure 3 As shown, screws 9 are fixed to both sides of the counterweight box 4 in the width direction. The screws 9 are located in the middle of the side wall of the counterweight box 4. A through hole 10 is opened on the lower crossbeam 6 corresponding to the position of the screw 9. The end of the screw 9 away from the counterweight box 4 passes through the through hole 10 and is threaded to a limit nut 11. The diameter of the limit nut 11 is larger than the diameter of the through hole 10. The counterweight box 4 adopts a detachable structure for easy disassembly and assembly. Specifically, unscrew the limit nut 11, pass the screw 9 through the through hole 10 from bottom to top, and finally screw the limit nut 11 on so that the limit nut 11 contacts the top surface of the lower crossbeam 6, thereby installing the counterweight box 4 on the lower crossbeam 6. Disassembly is simply done by unscrewing the limit nut 11 and removing the counterweight box 4.

[0031] Example 5

[0032] Based on Example 4, such as Figures 1 to 3As shown, a partition 12 is fixed inside the counterweight box 4, dividing the counterweight box 4 into a left chamber 13 and a right chamber 14 along its length. The belt is corrected by adjusting the weight difference between the left and right chambers 13 and 14. The square tube and U-shaped plate 7 are fitted with clearance. The counterweight box 4 is installed in the middle of the lower crossbeam 6, forming a left chamber 13 and a right chamber 14 inside. Different numbers of counterweight balls 8 are placed in the left and right chambers 13 and 14, causing the lower crossbeam 6 to experience an eccentric force from the counterweight box 4. The clearance fit between the square tube and the U-shaped plate 7 allows the sliding frame 2 to have left and right offset freedom on the fixed frame 1, placing the driven pulley 3 in an inclined state, which can correct the belt deviation. Due to prolonged operation, local wear may occur, causing the belt to gradually deviate. Furthermore, uneven material distribution, manufacturing errors, or frame deviations can also cause belt misalignment. By shifting the center of gravity of the counterweight, the force balance of the sliding frame 2 is altered, causing a slight offset of the driven pulley 3, thereby precisely correcting the belt's trajectory. This design not only eliminates the purchase and installation costs of independent correction equipment and simplifies the overall structure of large belt conveyors, but also reduces maintenance steps. It eliminates the need to maintain both the tensioning and correction devices simultaneously, reducing the workload and operational difficulty for maintenance personnel, and significantly improving the economy and convenience of equipment operation.

[0033] Furthermore, the clearance between the square tube and the U-shaped plate 7 is 1mm-5mm.

[0034] Example 6

[0035] Based on Example 5, such as Figures 1 to 4 As shown, both the left chamber 13 and the right chamber 14 are equipped with grid-like components. Each grid-like component includes multiple horizontal plates 15 and multiple vertical plates 16. The vertical plates 16 are fixedly passed through the horizontal plates 15. The multiple horizontal plates 15 and multiple vertical plates 16 are connected to form grid-like cavities. Each cavity can only hold one counterweight ball 8 on the horizontal plane. The grid-like components in the left chamber 13 and the right chamber 14 form independent cavities through the horizontal plates 15 and vertical plates 16, ensuring that each counterweight ball is accurately positioned and does not shift. This allows for quick determination of the number of counterweight balls 8 in the left chamber 13 and the right chamber 14. The number of counterweight balls 8 in the left chamber 13 and right chamber 14 is controlled according to the actual operating status of the belt. This avoids the problem that the number of counterweight balls 8 cannot be clearly judged due to their concentrated accumulation in the large volume chamber. Since only one counterweight ball 8 can be placed in an independent chamber on the horizontal plane, it is very inconvenient to take the counterweight ball 8. The setting of the connecting rod 17 solves this problem well. When placing the counterweight ball 8, the connecting rod 17 on the counterweight ball 8 is set upward, so that the counterweight ball 8 can be quickly taken and placed through the connecting rod 17.

Claims

1. An adjustable tensioning device for large belt conveyors, characterized in that The utility model provides a kind of belt tensioning device, including fixed frame (1) and sliding frame (2), the sliding frame (2) sliding installation is in fixed frame (1), driven pulley (3) is rotationally arranged on the sliding frame (2), the sliding frame (2) moves along the height direction of fixed frame (1), for adjusting the interval between driven pulley (3) and driving pulley, the bottom of the sliding frame (2) is provided with counterweight box (4), the tensioning degree of belt is adjusted by putting different number of counterweight ball (8) into counterweight box (4).

2. An adjustable tensioning device for large belt conveyors according to claim 1, characterized in that The fixed frame (1) includes two parallelly arranged square tubes, the square tubes are vertically fixedly installed, the sliding frame (2) includes an upper cross beam (5), a lower cross beam (6) and two U-shaped plates (7), two ends of the upper cross beam (5) are respectively fixedly connected to one end of the two U-shaped plates (7), two ends of the lower cross beam (6) are respectively fixedly connected to the other end of the two U-shaped plates (7), the square tubes are slidingly fitted into the U-shaped openings of the U-shaped plates (7), the side walls of the U-shaped plates (7) are fixedly provided with bearing seats (18), and two ends of the driven pulley (3) are respectively rotationally installed on the two bearing seats (18).

3. An adjustable tensioning device for large belt conveyors according to claim 2, characterized in that The two side walls of the counterweight box (4) in the width direction are fixedly provided with screw rods (9), the screw rods (9) are arranged at the middle portions of the side walls of the counterweight box (4), the lower cross beam (6) is provided with through holes (10) corresponding to the positions of the screw rods (9), one end of each screw rod (9) away from the counterweight box (4) is threadedly connected to a limiting nut (11) penetrating through the through hole (10), and the diameter of the limiting nut (11) is greater than that of the through hole (10).

4. A tensioner according to claim 3, wherein the tensioner is adapted to be used in a large belt conveyor. The counterweight box (4) is fixedly provided with a partition plate (12), the partition plate (12) divides the counterweight box (4) into a left chamber (13) and a right chamber (14) in the length direction of the counterweight box (4), and the deviation of the belt is corrected by adjusting the counterweight difference between the left chamber (13) and the right chamber (14).

5. An adjustable tensioning device for large belt conveyors according to claim 4, characterized in that The square tube and the U-shaped plate (7) are gap-fitted.

6. An adjustable tensioning device for large belt conveyors according to claim 5, characterized in that The fitting gap between the square tube and the U-shaped plate (7) is 1mm-5mm.

7. An adjustable tensioning device for large belt conveyors according to claim 4, characterized in that The left chamber (13) and the right chamber (14) are both provided with a grid assembly, the grid assembly includes a plurality of horizontal plates (15) and a plurality of vertical plates (16), the vertical plates (16) are fixedly penetrated through the horizontal plates (15), the plurality of horizontal plates (15) and the plurality of vertical plates (16) are connected to form a grid cavity, and each cavity can only place one counterweight ball (8) on a horizontal plane.

8. An adjustable tensioning device for large belt conveyors according to claim 4, characterized in that The counterweight ball (8) is fixedly provided with a connecting rod (17), and the connecting rod (17) is T-shaped.

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