Downwardly running belt conveyor

Abstract

The application discloses a downward conveying belt conveyor, comprising: a belt; a four-quadrant variable frequency driving system; a secondary drive brake; a tensioning device; and a control device. The downward conveying belt conveyor provided by the application can switch between driving mode and feedback mode through the four-quadrant variable frequency driving system, so that the gravitational potential energy in the downward conveying process can be converted into electric energy and fed back to the power grid, the operation cost is reduced, and efficient energy utilization is achieved. Moreover, the secondary drive brake is arranged to supplement the braking capacity of the four-quadrant variable frequency driving system in the feedback mode, and the control device can cooperatively control the four-quadrant variable frequency driving system, the secondary drive brake and the tensioning device according to the operation parameters of the belt, so that stable braking of the downward conveying belt conveyor under different load and slope conditions is ensured, belt stall, skidding or overload is avoided, safe shutdown is achieved, and the safety, energy-saving type, stability and intelligence of the downward conveying belt conveyor are effectively improved.

Description

Technical Field

[0001] This application relates to the field of transportation equipment technology, and more particularly to a downconducting belt conveyor. Background Technology

[0002] During operation, the component of the material's gravity along the conveying direction will drive the conveyor belt to accelerate downwards, which can easily lead to accidents such as "runaway" loss of control, belt overlap, and tearing in case of shutdown or emergency.

[0003] Existing technologies employ fixed braking force designs that do not consider the dynamic impact of load fluctuations (such as changes in material quantity and slope differences) on braking requirements. For example, the calculation of transmission braking force is based solely on the maximum static load, completely ignoring the influence of acceleration changes on belt tension. This can easily lead to belt slippage or breakage during braking. Furthermore, existing technologies all use hydraulic or mechanical braking to dissipate energy through friction on the belt, which can easily cause the system to overheat, resulting in poor braking performance and an inability to recover energy.

[0004] Therefore, it needs to be improved. Utility Model Content

[0005] This application provides a downward belt conveyor to address the technical problems of unreliable braking and inability to recover energy mentioned in the background art.

[0006] This application provides a downward conveyor belt, comprising: adhesive tape; The four-quadrant variable frequency drive system is connected to the conveyor belt. The four-quadrant variable frequency drive system has a drive mode and a feedback mode. When the four-quadrant variable frequency drive system is in drive mode, it can drive the conveyor belt to run. When the four-quadrant variable frequency drive system is in feedback mode, it can obtain the kinetic energy of the conveyor belt and generate electricity. The auxiliary drive brake is connected to the belt and can apply braking torque to the belt. The tensioning device is connected to the tape and can adjust the tension of the tape. The control device is capable of acquiring the operating parameters of the conveyor belt. The control device is electrically connected to the four-quadrant frequency converter drive system, the auxiliary drive brake, and the tensioning device. The control device controls the four-quadrant frequency converter drive system, the auxiliary drive brake, and the tensioning device according to the operating parameters.

[0007] Furthermore, the downward conveyor belt has both electric and power generation modes: When the current belt conveyor is in electric mode, the four-quadrant frequency conversion drive system switches to drive mode, the auxiliary drive brake is in standby mode, and the tensioning device is dynamically adjusted. When the conveyor belt is in power generation mode, the four-quadrant frequency conversion drive system switches to feedback mode. The auxiliary drive brake switches its working state according to the real-time speed of the belt, and the tensioning device adjusts the tension of the belt to keep the belt under positive tension at the approach point of the auxiliary drive brake.

[0008] Furthermore, the downward-facing belt conveyor also features an emergency stop function, and the four-quadrant variable frequency drive system has an S-curve speed reduction mode. When the conveyor belt switches to emergency stop mode, the four-quadrant variable frequency drive system switches to S-curve deceleration mode, the auxiliary drive brake applies maximum braking torque to the belt, and the tensioning device tensions the belt within the first preset time.

[0009] Furthermore, the first preset time ranges from 0.5s to 1s.

[0010] Furthermore, the control device includes a speed encoder and a load cell. The speed encoder can acquire the real-time speed parameters of the conveyor belt, and the load cell can acquire the load distribution parameters on the conveyor belt. The real-time speed parameters and the load distribution parameters constitute the operating parameters.

[0011] Furthermore, the auxiliary drive brake has at least two braking positions, at least one of which is capable of applying the maximum braking torque to the belt, and at least one of which is capable of applying 20% ​​to 50% of the maximum braking torque to the belt.

[0012] Furthermore, the control device also includes a tension sensor, which can acquire the tension parameters of the tape, and the tension parameters constitute the operating parameters.

[0013] Furthermore, the down-conveying belt conveyor also includes a drive drum, with the belt mounted on the drive drum, and a secondary drive brake mechanically connected to the drive drum.

[0014] Furthermore, the auxiliary drive brake is located at the tail section of the lower belt conveyor or in the middle section of the lower belt conveyor.

[0015] Furthermore, the secondary drive brake includes a hydraulic disc brake structure or a hysteresis brake structure.

[0016] The downconducting belt conveyor provided in this application, by setting a four-quadrant variable frequency drive system, can switch between drive mode and feedback mode, thereby converting the gravitational potential energy during the downconducting process into electrical energy and feeding it back to the power grid, reducing operating costs and achieving efficient energy utilization. Furthermore, a secondary drive brake is set up to supplement the braking capacity of the four-quadrant variable frequency drive system in feedback mode. The linkage between the secondary drive brake and the tensioning device can serve as a redundancy design for the four-quadrant variable frequency drive system, ensuring the operational reliability of the downconducting belt conveyor. In particular, the control device can coordinate the control of the four-quadrant variable frequency drive system, the secondary drive brake, and the tensioning device according to the belt's operating parameters, ensuring stable braking of the downconducting belt conveyor under different load and slope conditions, avoiding belt stall, slippage, or overload, and achieving safe shutdown. This effectively improves the safety, energy efficiency, stability, and intelligence of the downconducting belt conveyor. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a downward conveyor belt provided in an embodiment of this application; Explanation of reference numerals in the attached figures: 1. Adhesive tape; 2. Four-quadrant variable frequency drive system; 3. Secondary drive brake; 4. Tensioning device; 5. Control device. Detailed Implementation

[0018] The present application / disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application / disclosure and are not intended to limit the scope of the present application / disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present application / disclosure are shown in the accompanying drawings, not the entire structure.

[0019] like Figure 1As shown in the embodiment of this application, a downward conveyor belt is provided, including: a conveyor belt 1; a four-quadrant variable frequency drive system 2, which is connected to the conveyor belt 1. The four-quadrant variable frequency drive system 2 has a drive mode and a feedback mode. When the four-quadrant variable frequency drive system 2 is in drive mode, it can drive the conveyor belt 1 to run. When the four-quadrant variable frequency drive system 2 is in feedback mode, it can obtain the kinetic energy of the conveyor belt 1 and generate electricity; and a secondary drive brake. Device 3, the auxiliary drive brake 3 is connected to the conveyor belt 1, and the auxiliary drive brake 3 can apply braking torque to the conveyor belt 1; tensioning device 4, the tensioning device 4 is connected to the conveyor belt 1, and the tensioning device 4 can adjust the tension of the conveyor belt 1; control device 5, the control device 5 can acquire the operating parameters of the conveyor belt 1, the control device 5 is electrically connected to the four-quadrant variable frequency drive system 2, the auxiliary drive brake 3 and the tensioning device 4, and the control device 5 controls the four-quadrant variable frequency drive system 2, the auxiliary drive brake 3 and the tensioning device 4 according to the operating parameters. By setting up a four-quadrant variable frequency drive system 2, which can switch between drive mode and feedback mode, the gravitational potential energy during the downward conveying process can be converted into electrical energy and fed back to the power grid, reducing operating costs and achieving efficient energy utilization. Moreover, the auxiliary drive brake 3 is set up to supplement the braking capacity of the four-quadrant variable frequency drive system 2 in feedback mode. The linkage between the auxiliary drive brake 3 and the tensioning device 4 can serve as a redundancy design for the four-quadrant variable frequency drive system 2, ensuring the working reliability of the downward conveyor belt. In particular, the control device 5 can coordinate the control of the four-quadrant variable frequency drive system 2, the auxiliary drive brake 3, and the tensioning device 4 according to the operating parameters of the belt 1, ensuring stable braking of the downward conveyor belt under different load and slope conditions, avoiding belt 1 stalling, slippage, or overload, and achieving safe shutdown. This effectively improves the safety, energy saving, stability, and intelligence of the downward conveyor belt.

[0020] like Figure 1 As shown, the conveyor belt 1 is arranged in a ring and passes through the four-quadrant variable frequency drive system 2, the auxiliary drive brake 3 and the tensioning device 4 in sequence. This allows the four-quadrant variable frequency drive system 2 and the auxiliary drive brake 3 to directly adjust the operation of the conveyor belt 1. At the same time, the tensioning device 4 can adjust the tension of the conveyor belt 1 by pulling and releasing it. The rollers used to support the conveyor belt 1 are not shown in the figure, but can be set according to the actual position requirements.

[0021] Furthermore, the downward conveyor belt has both electric and power generation modes: When the current conveyor belt is in electric mode, the four-quadrant variable frequency drive system 2 switches to drive mode, the auxiliary drive brake 3 is in standby mode, and the tensioning device 4 is dynamically adjusted. At this time, the four-quadrant variable frequency drive system 2 drives the belt 1 to run, the auxiliary drive brake 3 does not need to work, and the tensioning device 4 only needs to be adjusted according to the tension characteristics of the belt 1. When the current conveyor belt is in power generation mode, the four-quadrant variable frequency drive system 2 switches to feedback mode. The auxiliary drive brake 3 switches its working state according to the real-time speed of the belt 1. The tensioning device 4 adjusts the tension of the belt 1 to keep the belt 1 under positive tension at the approach point of the auxiliary drive brake 3. At this time, the belt 1 drives the four-quadrant variable frequency drive system 2 to generate electricity. The auxiliary drive brake 3 supplements the braking force provided by the four-quadrant variable frequency drive system 2 to the belt 1. The tensioning device 4 adjusts the negative tension on the belt 1 so that the drive rolling approach point always maintains positive tension. Preferably, the tension at the slack side approach point is always ≥1kN / m to avoid slippage and roll slippage.

[0022] The down-conveying belt conveyor includes four operating conditions: full-section no-load, up-conveying full-load / down-conveying no-load, up-conveying no-load / down-conveying full-load, and full-section full-load. When the down-conveying belt conveyor is in the full-section no-load or up-conveying full-load / down-conveying no-load condition, it is in electric mode. When the down-conveying belt conveyor is in the up-conveying no-load / down-conveying full-load or full-section full-load condition, it is in power generation mode.

[0023] When the current conveyor belt is in a fully unloaded condition, the slack side of the belt 1 is at the point of departure. At this time, the tension is uniform and the tension force is stable. At this time, the tensioning device 4 can maintain the current state, and the control device 5 needs to maintain low-speed operation to avoid starting impact. When the conveyor belt is in the condition of full load on the upper section and no load on the lower section, the slack side of the belt 1 is at the point of slippage. At this time, the tension of the upper section is high and the tension of the lower section is low. The control device 5 needs to control the four-quadrant frequency conversion drive system 2 to increase the drive torque to prevent the upper section from slipping. The tensioning device 4 can maintain the current state.

[0024] When the conveyor belt is in an up-loading unloaded / down-loading full-loaded condition, the slack side of the belt 1 is at the approach point. At this time, the down-loading section is under negative tension and the unloading section is relaxed. At this time, the tensioning device 4 needs to increase the tension of the belt 1 and adjust the negative tension of the down-loading section to positive tension so that the auxiliary drive brake 3 can smoothly generate braking torque on the belt 1.

[0025] When the conveyor belt is operating at full load, the slack side of belt 1 is at the approach point. At this time, the entire machine is under negative tension and is prone to stalling. The system needs to determine whether to generate electricity based on the downward tilt angle. The four-quadrant variable frequency drive system 2 feeds back the electrical energy generated by the motor to the DC bus through the inverter unit, causing the DC bus voltage to rise. If this voltage exceeds a set threshold, the inverter control logic will determine that the system is in a power generation state. At this point, the four-quadrant variable frequency drive system 2 needs to apply braking torque to belt 1, while the auxiliary drive brake 3 supplements the braking torque, and the tensioning device 4 compensates for the tension of belt 1.

[0026] The control device 5 can learn the tension change pattern based on historical data, predict load fluctuations, and adjust the tension in advance.

[0027] Furthermore, the downward-facing belt conveyor also features an emergency stop function, and the four-quadrant variable frequency drive system 2 has an S-curve speed reduction mode. When the lower belt conveyor switches to emergency stop mode, the four-quadrant variable frequency drive system 2 switches to S-curve deceleration mode, the auxiliary drive brake 3 applies maximum braking torque to the belt 1, and the tensioning device 4 tensions the belt 1 within a first preset time. When the speed fluctuation of the belt 1 is ≥±5% or the real-time speed of the belt 1 exceeds 110% of the rated speed, it is determined that the belt 1 has a stall problem and the lower belt conveyor needs to be stopped urgently. At this time, the four-quadrant variable frequency drive system 2 decelerates according to the S-curve to avoid dynamic tension impact. The auxiliary drive brake outputs maximum braking torque to stop the belt 1. At the same time, in order to avoid the belt 1 decelerating too quickly and generating tension impact, the tensioning device 4 quickly tensions the belt 1, rapidly increasing the sag resistance of the belt 1, offsetting the downward conveying force, avoiding impact load, preventing the belt 1 from slack and accumulating, and also preventing the belt 1 from breaking. The response time from detecting stall to executing an emergency stop is ≤0.5s, and the speed fluctuation is controlled within ±5%, effectively reducing mechanical shock. The four-quadrant variable frequency drive system 2 performs soft braking, the auxiliary drive brake 3 performs graded braking, and the tension buffer of the tensioning device 4 effectively reduces the dynamic load during emergency stops, reduces the wear of the conveyor belt 1, rollers, and bearings, ensures stability, and reduces the overall failure rate by more than 30%.

[0028] The acceleration range during the S-curve deceleration is 0.1 m / s² to 0.3 m / s².

[0029] Preferably, the judgment condition for determining when tape 1 is stalled is: the real-time speed of tape 1 is 110% of the rated speed and the tension at the approach point is <1kN / m.

[0030] Furthermore, the first preset time ranges from 0.5s to 1s. This means that the tensioning device 4 quickly increases the tension of the tape 1, increases the sagging resistance, counteracts the negative tension, and ensures the reliability of the tape 1.

[0031] After the lower belt conveyor is braked and stabilized, the tensioning device 4 slowly releases the tension to avoid impact on the belt 1. That is, when the lower belt conveyor switches to emergency stop mode, the tensioning device 4 adopts the "fast pull and slow release" working process, which effectively ensures the reliability of the belt 1 while braking.

[0032] Optionally, the auxiliary drive brake 3 has at least two braking positions, at least one of which can apply the maximum braking torque to the conveyor belt 1, and at least one braking position can apply 20% to 50% of the maximum braking torque to the conveyor belt 1. That is, the auxiliary drive brake 3 can apply an adjustable braking torque to the conveyor belt 1. When the conveyor belt is in power generation mode, the auxiliary drive brake 3 dynamically applies the braking torque according to the real-time speed of the conveyor belt 1. For example, it initially applies 20% to 50% of the braking torque, and if the real-time speed of the conveyor belt 1 continues to rise, it gradually increases to 100%. The change in braking torque between the braking positions in the auxiliary drive brake 3 can be 1% or 5% of the maximum braking torque.

[0033] In one implementation, the control device 5 includes a speed encoder and a load cell. The speed encoder acquires the real-time speed parameters of the conveyor belt 1, and the load cell acquires the load distribution parameters on the conveyor belt 1. The real-time speed parameters and load distribution parameters constitute the operating parameters. By comparing the real-time speed parameters of the conveyor belt 1 with the preset speed parameters, the current running direction of the conveyor belt 1 and whether it is overspeeding can be determined. The load distribution parameters can be used to judge the load distribution of the upper and lower sections of the conveyor belt, thereby distinguishing the current operating conditions of the conveyor belt.

[0034] Furthermore, the control device 5 also includes a tension sensor, which can acquire the tension parameters of the conveyor belt 1, and these tension parameters constitute the operating parameters. By monitoring the tension at the approach / departure point of the drive roller, the risk of negative tension in the conveyor belt 1 can be identified.

[0035] Furthermore, the downward-facing belt conveyor also includes a drive roller, with the belt 1 mounted on it, and the auxiliary drive brake 3 mechanically connected to the drive roller. This mechanical connection allows for better transmission of the braking torque of the auxiliary drive brake 3 to the belt 1, reducing braking delay and improving response speed; the response time can be less than or equal to 0.3 seconds.

[0036] Furthermore, the auxiliary drive brake 3 is located at the tail end of the lower belt conveyor or in the middle of the lower belt conveyor. This allows for better distribution of the braking torque of the four-quadrant variable frequency drive system 2 and the torque of the auxiliary drive brake 3, prioritizing the power generation capacity of the four-quadrant variable frequency drive system 2 and reducing the energy consumption of the lower belt conveyor.

[0037] Furthermore, the auxiliary drive brake 3 includes a hydraulic disc brake structure or a hysteresis brake structure.

[0038] The control device 5 can be a PLC or an industrial PLC. Based on the working conditions of the conveyor belt, it dynamically calculates the braking torque, tension force and drive strategy to realize the coordinated operation of the four-quadrant frequency conversion drive system, the auxiliary drive brake and the tensioning device.

[0039] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A downward conveyor belt, characterized in that: include: Adhesive tape (1); The four-quadrant variable frequency drive system (2) is connected to the conveyor belt (1). The four-quadrant variable frequency drive system (2) has a drive mode and a feedback mode. When the four-quadrant variable frequency drive system (2) is in the drive mode, the four-quadrant variable frequency drive system (2) can drive the conveyor belt (1) to run. When the four-quadrant variable frequency drive system (2) is in the feedback mode, the four-quadrant variable frequency drive system (2) can obtain the kinetic energy of the conveyor belt (1) and generate electricity. A secondary drive brake (3) is connected to the belt (1) and the secondary drive brake (3) is capable of applying braking torque to the belt (1); Tensioning device (4), which is connected to the tape (1) and can adjust the tension of the tape (1); The control device (5) is capable of acquiring the operating parameters of the tape (1). The control device (5) is electrically connected to the four-quadrant variable frequency drive system (2), the auxiliary drive brake (3) and the tensioning device (4). The control device (5) controls the four-quadrant variable frequency drive system (2), the auxiliary drive brake (3) and the tensioning device (4) according to the operating parameters.

2. The downward conveyor belt according to claim 1, characterized in that: The downstream belt conveyor has both electric mode and power generation mode: When the lower belt conveyor is in the electric mode, the four-quadrant frequency conversion drive system (2) switches to the drive mode, the auxiliary drive brake (3) is in standby mode, and the tensioning device (4) is dynamically adjusted. When the lower belt conveyor is in the power generation mode, the four-quadrant frequency conversion drive system (2) switches to the feedback mode, the auxiliary drive brake (3) switches the working state according to the real-time speed of the belt (1), and the tensioning device (4) adjusts the tension of the belt (1) to keep the belt (1) under positive tension at the approach point of the auxiliary drive brake (3).

3. The downward conveyor belt according to claim 1, characterized in that: The down-conveying belt conveyor also has an emergency stop function, and the four-quadrant frequency conversion drive system (2) has an S-curve speed reduction mode: When the conveyor belt switches to the emergency stop condition, the four-quadrant variable frequency drive system (2) switches to the S-curve speed reduction mode, the auxiliary drive brake (3) applies the maximum braking torque to the belt (1), and the tensioning device (4) tensions the belt (1) within a first preset time.

4. The downward conveyor belt according to claim 3, characterized in that: The first preset time ranges from 0.5s to 1s.

5. The downward conveyor belt according to claim 1, characterized in that: The auxiliary drive brake (3) has at least two braking positions, at least one of the braking positions is capable of applying the maximum braking torque to the belt (1), and at least one of the braking positions is capable of applying 20% ​​to 50% of the maximum braking torque to the belt (1).

6. The downward conveyor belt according to claim 1, characterized in that: The control device (5) includes a speed encoder and a load cell. The speed encoder can acquire the real-time speed parameters of the tape (1), and the load cell can acquire the load distribution parameters on the tape (1). The real-time speed parameters and the load distribution parameters constitute the operating parameters.

7. The downward conveyor belt according to claim 1, characterized in that: The control device (5) further includes a tension sensor, which is capable of acquiring the tension parameters of the tape (1), and the tension parameters constitute the operating parameters.

8. The downward conveyor belt according to claim 1, characterized in that: The down-conveying belt conveyor also includes a drive roller, the belt (1) is disposed on the drive roller, and the auxiliary drive brake (3) is mechanically connected to the drive roller.

9. The downward conveyor belt according to claim 1, characterized in that: The auxiliary drive brake (3) is located at the tail section of the lower belt conveyor or in the middle section of the lower belt conveyor.

10. The downward conveyor belt according to claim 1, characterized in that: The auxiliary drive brake (3) includes a hydraulic disc brake structure or a hysteresis brake structure.

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