A control method for precisely adjusting a belt machine discharging point based on pressure detection

Abstract

The present application relates to a kind of control method of accurate adjustment belt feeder material drop point based on pressure detection, the method comprises the following steps: step 1: first, two groups of weighing detection devices are installed at the belt roller support (14) before downstream belt hopper, utilize existing roller to be modified into weighing roller;Step 2: second, the pressure value measured in situ is fed back to PLC analog module by pressure data converter, and enters the program segment application, step 3: finally, proportional amplifier signal drives proportional hydraulic valve (17) to control hydraulic push rod (18) and drive movable baffle (19) to carry out extension or retraction movement, until the adjustment signal stops to reach a steady state;The technical scheme realizes the full-automatic accurate control to belt feeder material drop point, effectively relieves belt deviation and material overflow problem, simultaneously reduces personnel labor intensity, provides new ideas and feasible method for belt feeder material drop point control.

Description

Technical Field

[0001] This invention relates to a control method, specifically a control method for precisely adjusting the material drop point of a belt conveyor based on pressure detection, belonging to the field of belt conveyor technology. Background Technology

[0002] Belt conveyors typically transport over a dozen types of materials, including pellets, lump ore, and fines. However, during the upstream and downstream transport processes, material deviation frequently occurs on the belt conveyor. This results in uneven distribution of force along the belt's centerline, leading to belt misalignment, wear, and severe material spillage, thus disrupting normal production operations.

[0003] The main reason for this is that the material drop point changes due to the offset of the impact point in the chute during the upstream and downstream transmission processes, resulting in uneven material distribution on the belt. Therefore, only by effectively controlling the position of the initial impact point can the uniform distribution of material drop points on the belt be ensured. Patent 201120159597.6 describes a device for changing the material drop position by installing a serrated push rod positioning steel plate through an opening in the upstream belt dust cover. However, this device relies entirely on manual operation and lacks reasonable automatic adjustment. On the one hand, the accuracy of material drop point control needs to be improved; on the other hand, it increases the labor intensity of personnel. Therefore, a scientific and effective method for controlling the material drop point is urgently needed to completely solve the above problems. Summary of the Invention

[0004] This invention addresses the problems existing in the prior art by providing a control method for precisely adjusting the material drop point of a belt conveyor based on pressure detection. This technical solution can effectively utilize the pressure signal of material transmission to achieve fully automatic and precise control of the material drop point of the belt conveyor, effectively alleviate belt misalignment and material spillage problems, and reduce the labor intensity of personnel, providing a new idea and feasible method for the control of the material drop point of a belt conveyor.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: a control method for precisely adjusting the material drop point of a belt conveyor based on pressure detection, characterized in that the method includes the following steps:

[0006] Step 1: First, as shown in the figure above, install two sets of weighing detection devices (1 and 2) at the belt idler bracket (14) in front of the downstream belt hopper, and modify the existing idler into a weighing idler. Install two sets of special pressure sensors on the idler brackets on both sides of the belt in weighing areas 4 and 5 to measure the pressure value of the material on both sides of the belt. When the material is spilled from the hopper onto the belt and passes through the weighing roller area (1 and 2), the pressure sensors on both sides measure the pressure feedback value and read the left and right pressure data within a certain area.

[0007] Step 2: Next, as shown in the diagram above, the pressure value measured on-site is fed back to the PLC analog module via a pressure data converter and entered into the program segment. The pressure deviation value is set through the calculation and comparator function blocks. If the deviation exceeds the range, a given adjustment signal is output to the proportional valve amplifier board as the feedback control quantity for the on-site hydraulic proportional valve. The pressure value on the left side of the module serves as one input signal for the adder / subtractor 4 and also as one input signal for the left pressure comparator 7. The pressure value on the right side is output through an inverter as the other input signal for the adder / subtractor 4 and also as one input signal for the right pressure comparator 8. If there is a deviation between the two pressure values, the adder / subtractor 4 outputs a positive or negative value, which is then entered into the differential pressure comparator 6 for judgment, outputting a digital signal of 0 or 1 (0 for no deviation, 1 for deviation). The other input of the aforementioned left and right pressure values ​​is compared with the left and right pressure setpoints at pressure comparators 7 or 8, and similarly outputs a digital signal of 0 or 1 (0 for within tolerance, 1 for exceeding tolerance). The digital signal output by pressure deviation comparator 6 is compared with the left and right pressure deviation digital signals respectively through AND gate 9 or 10 to determine whether the output is 0 or 1 (0 for blocking, 1 for unlocking). If the left side is unlocked, the setpoint regulator output sends a directional adjustment signal to the proportional amplifier; if the right side is unlocked, the setpoint regulator output sends a reverse adjustment signal to the proportional amplifier, until the AND gate output is zero and the proportional amplifier valve core returns to its original position to stop the adjustment signal.

[0008] Step 3: Finally, as shown in the diagram above, the proportional amplifier signal drives the proportional hydraulic valve to control the hydraulic push rod and move the movable baffle to extend or retract until the adjustment signal stops and a steady state is reached. By determining the positive and negative polarities, the given command is controlled by the amplifier board's pressure-flow conversion to provide two adjustable control voltages, U1 and U2, to the positive and negative terminals of the proportional valve L, achieving bidirectional drive of the valve core. This adjusts the speed of the hydraulic push rod's extension and retraction, precisely adjusting the material drop point position.

[0009] Compared to existing technologies, this invention has the following advantages: First, it utilizes two adjacent sets of idlers on the downstream conveyor frame as weighing rollers. The weight of the material is measured by connecting pressure sensors to weighing supports on both sides of the belt. The material weight is transmitted to the pressure sensors on both sides of the belt via a lever system of idlers and weighing supports. The magnitude of the force depends not only on the lever system but also on the load on the idlers, which is actually the instantaneous weight of the material on a section of the belt of length L. The effect of pressure. for:

[0010]

[0011] in, It reflects the weight of an area rather than the weight of a single point, making the data measurement more reliable.

[0012] Secondly, the on-site weighing module measures the pressure values ​​on both sides of the belt, which are then transmitted to the PLC analog module via a transmitter. The program reads this value and the comparison module outputs a pressure difference as feedback for the proportional hydraulic control valve. When the belt drop point deviates from its normal range and exceeds the pressure difference range, the proportional valve begins to control the hydraulic actuator for adjustment. As the pressure difference feedback decreases back to the normal range, the proportional valve closes, and the hydraulic actuator stops adjusting. At this point, the movable baffle remains at a relatively stable adjustment angle.

[0013] Finally, by comparing the measured data from the pressure sensor, the positive and negative directions of the pressure on both sides are determined, and the extension and retraction of the hydraulic push rod are controlled to achieve precise positioning. At the same time, the proportional valve controlled by the PLC program is used to achieve stepless speed regulation of the hydraulic push rod.

[0014] This invention uses a detection unit to detect the pressure of materials on a belt conveyor, a control unit to provide feedback adjustment for pressure deviation, and a drive unit to adjust the speed of the hydraulic push rod's extension and retraction, thereby precisely adjusting the material drop point position. This control method can automatically control the material drop point of the belt conveyor, effectively preventing belt misalignment and material spillage. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the control flow of the present invention;

[0016] Figure 2 A schematic diagram illustrating the precise control of the material drop point on the belt conveyor;

[0017] Figure 3 , Figure 4 Installation distribution diagram for the detection unit;

[0018] Figure 5 This is a logic diagram of the control unit;

[0019] Figure 6 Drive unit control diagram.

[0020] In the diagram: 1 is the first weighing idler, 2 is the second weighing idler, 3 is the reverse sign device, 4 is the adder / subtractor, 5 is the absolute value, 6 is the differential pressure comparator, 7 is the left pressure comparator, 8 is the right pressure comparator, 9 is the left AND gate, 10 is the right AND gate, 11 is the output of the left unsealing setpoint regulator, 12 is the output of the right unsealing setpoint regulator, 13 is the proportional amplifier, 14 is the weighing bracket, 15 is the left pressure sensor, 16 is the right pressure sensor, 17 is the proportional hydraulic valve, and 18 is the hydraulic push rod. Detailed Implementation

[0021] To enhance understanding of the present invention, the embodiments will be described in detail below with reference to the accompanying drawings.

[0022] Example 1: See Figure 1 This invention discloses a control method for precisely adjusting the material drop point of a belt conveyor based on pressure detection. The method measures the pressure signal transmitted by the material in the weighing area of ​​the belt, feeds it back to a PLC program for calculation and comparison, and utilizes multiple functional modules to output control proportional valves to drive hydraulic push rods to adjust movable baffles, thereby precisely controlling the material drop point position. This effectively prevents belt misalignment and material spillage. The method includes the following steps: [The text abruptly ends here, likely due to an incomplete sentence or missing information.] Figures 1-4 ,

[0023] Step 1: First, see Figure 3 , Figure 4 A first weighing idler 1 and a second weighing idler 2 are installed at the belt idler bracket in front of the downstream conveyor hopper, converting existing idlers into weighing idlers. Two sets of dedicated pressure sensors, namely a left pressure sensor 7 and a right pressure sensor 8, are installed on the idler brackets on both sides of the belt in the weighing area to measure the pressure value of the material on both sides of the belt. When material is spilled from the hopper onto the belt and passes through the weighing roller area, the left and right pressure sensors measure the pressure feedback value and read the left and right pressure data within a certain area.

[0024] Step 2: Secondly, such as Figure 5 The pressure value measured on-site is fed back to the PLC analog module via a pressure data converter and then applied to the program segment. The pressure deviation value is set through the calculation and comparator function blocks. If the deviation exceeds the range, a given adjustment signal is output to the proportional valve amplifier board as the feedback control quantity for the on-site hydraulic proportional valve. The pressure value on the left side of the module serves as one input signal to the adder / subtractor 4 and also as one input signal to the left pressure comparator 7. The pressure value on the right side is output through the inverter 3 and serves as the other input signal to the adder / subtractor 4 and also as one input signal to the right pressure comparator 8. If there is a deviation between the two pressure values, the adder / subtractor 4 outputs a positive or negative value, which is then entered into the differential pressure comparator 6 for judgment, outputting a digital signal of 0 or 1 (0 for no deviation, 1 for deviation). The other input of the aforementioned left and right pressure values ​​is compared with the left and right pressure setpoints at pressure comparators 7 or 8, and similarly outputs a digital signal of 0 or 1 (0 for within tolerance, 1 for exceeding tolerance). The digital signal output by differential pressure comparator 6, along with the left and right pressure over-tolerance digital signals, is used by AND gate 9 or 10 to determine whether the output is 0 or 1 (0 for blocking, 1 for unlocking). If the left side unlocks, the setpoint controller output sends a directional adjustment signal to proportional amplifier 13; if the right side unlocks, the setpoint controller output 12 sends a reverse adjustment signal to proportional amplifier 13. This continues until the AND gate output is zero (blocking), at which point the proportional amplifier valve core returns to its original position and stops adjusting.

[0025] Step 3: Finally, as shown in the diagram above, the proportional amplifier signal drives the proportional hydraulic valve 17 to control the hydraulic push rod 18 and move the movable baffle 19 to extend or retract until the adjustment signal stops and a steady state is reached. By determining the positive and negative polarities, the given command is controlled by the amplifier board's pressure-flow conversion to provide two adjustable control voltages, U1 and U2, to the positive and negative terminals of the proportional valve L, achieving bidirectional drive of the valve core. This adjusts the speed of the hydraulic push rod's extension and retraction, precisely adjusting the material drop point position.

[0026] It should be noted that the above embodiments are not intended to limit the scope of protection of the present invention. Equivalent transformations or substitutions made based on the above technical solutions all fall within the scope of protection of the claims of the present invention.

Claims

1. A control method for precisely adjusting the discharge point of a belt conveyor based on pressure detection, characterized in that, The method comprises the following steps: Step 1: First, install two sets of weighing detection devices at the belt roller support (14) in front of the downstream belt hopper, and modify the existing roller into a weighing roller; Step 2: Secondly, the pressure value measured on site is fed back to the PLC analog module through a pressure data converter and applied to a program segment, Step 3: Finally, the proportional amplifier signal drives the proportional hydraulic valve (17) to control the hydraulic push rod (18) and drive the movable baffle (19) to extend or retract until the adjustment signal stops to reach a steady state, In step 1, two sets of special pressure sensors, i.e. left pressure sensor (15) and right pressure sensor (16), are installed on the roller supports on both sides of the weighing area to measure the pressure values of the materials on both sides of the belt, and when the materials fall from the hopper onto the belt and pass through the weighing roller area, the left and right pressure sensors measure the pressure feedback values and read the left and right pressure data within a certain area, In step 2, the pressure deviation value is set through the operation and comparator function block, and the given adjustment signal is output to the proportional valve amplifier board when the range is exceeded, which is used as the feedback control amount of the on-site hydraulic proportional valve. The left pressure value in the module is used as the input signal of one end of the adder-subtracter (4) and as the input signal of one end of the left pressure comparator (7). The right pressure value is output through the inverter (3) as the input signal of the other end of the adder-subtracter (4) and as the input signal of one end of the right pressure comparator (8). When there is a deviation between the pressure values on both sides, the adder-subtracter (4) outputs a positive or negative value into the pressure difference comparator (6) for judgment, outputting a digital signal of 0 or 1, where 0 represents no deviation and 1 represents deviation. The other input ends of the left and right pressure values are connected to the left and right pressure comparators, respectively, and the left and right pressure set values are compared to output a digital signal of 0 or 1, where 0 represents no deviation and 1 represents deviation. The digital signal output by the pressure difference comparator (6) is connected to the left and right pressure deviation digital signals through the left and right AND gates to output 0 or 1, where 0 represents locking and 1 represents unlocking. When the left side is unlocked, the given regulator output (11) sends a directional adjustment signal to the proportional amplifier (13). When the right side is unlocked, the given regulator output (12) sends a reverse directional adjustment signal to the proportional amplifier (13). Until the AND gate output is zero, the proportional amplifier valve core returns to the original position and stops the adjustment signal. In step 3, through the judgment of positive and negative polarities, the given command is converted by the amplifier to control the positive and negative polarities of the proportional valve L to provide two adjustable control voltages U1 and U2, realize the bidirectional driving of the valve core, and adjust the speed of the hydraulic push rod extension and retraction to accurately adjust the material falling point position.

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