Belt conveyor control method based on material flow monitoring

Abstract

The present invention discloses a belt conveyor control method based on material flow monitoring, which can reduce the idling time of the belt conveyor and equipment wear, and save energy consumption. The control method is used to control the belt conveyors of each level to start up in sequence from back to front, and several belt conveyors are connected end to end to form a conveying system. The method includes the following steps: establishing a material flow database; based on the established material flow database, detecting and obtaining the material flow Q(x, t) of a fixed position A of the current belt conveyor at a certain time t; based on the material flow Q_x of the current belt conveyor, a controller controls the previous belt conveyor to start up, so that the material is transported from the current belt conveyor to the previous belt conveyor.

Description

Technical Field

[0001] The present invention relates to the technical field of belt conveyors, and in particular to a belt conveyor control method based on material flow monitoring. Background Art

[0002] Belt conveyors are the main equipment for transporting bulk materials. In actual applications, multiple belt conveyors are used to form a front-to-back material transportation system. The common belt conveyor control method based on material flow monitoring on the market generally uses the front and back stage control loops to be connected in series. The front stage belt conveyor can only be started after the front stage belt conveyor is started to avoid material blockage accidents. Figure 1 When starting a conveyor, it must be started against the direction of material flow, starting conveyors 1, 2, 3, 4, and so on. After all conveyors are started, the feed port is opened and material transport begins. With this method, the preceding conveyor idles until the material is transported to the preceding conveyor. Conveyor lines at actual production sites often stretch for several to tens of kilometers. Prolonged idling of conveyor belts can lead to increased equipment wear and waste of energy. Summary of the Invention

[0003] In view of the above problems existing in the prior art, the present invention provides a belt conveyor control method based on material flow monitoring, which can reduce the idling time and equipment wear of the belt conveyor and save energy consumption.

[0004] To achieve the above-mentioned object, the present invention adopts the following technical solution: a belt conveyor control method based on material flow monitoring, the control method is used to control the belt conveyors of each level to start sequentially from back to front, and a plurality of belt conveyors are connected end to end to form a conveying system, characterized in that the method includes the following steps:

[0005] A belt conveyor control method based on material flow monitoring is used to control the start-up of belt conveyors at all levels from back to front in sequence, with multiple belt conveyors connected end to end to form a conveying system. The method is characterized in that it includes the following steps:

[0006] S1. Divide the conveyor belts of each belt conveyor into several segments. Each segment is represented by a sequentially arranged logical segment number Bx, B1, B2, ..., Bn, where n is a positive integer. Preset a safe position A_safe and a fixed position A on each belt conveyor. The fixed position A is the material flow collection location. The safe position A_safe is located near the discharge port of each belt conveyor.

[0007] S2. Sequentially position each conveyor belt segment at a fixed position A in the current belt conveyor, record the time t corresponding to the positioning, and obtain the logical segment number Bx. Simultaneously, collect the material flow rate carried by the logical conveyor belt segment passing through the fixed position A at the time t, record it as Q[Bx,t], and store it in the material flow database;

[0008] S3. During the operation of the current belt conveyor, at a certain time t', locate the logical segment of the conveyor belt that passes through the safe position A_safe, obtain the logical segment number Bx' of the logical segment of the conveyor belt, and retrieve the latest data record Q[Bx',t] of the conveyor belt logical segment Bx' based on the established material flow database. Therefore, the material flow rate carried by the conveyor belt corresponding to the safe position A_safe of the current belt conveyor is Q[Bx',t].

[0009] S4. Determine whether the material flow Q[Bx',t] of the current belt conveyor is greater than zero. If so, it indicates that the current belt conveyor is carrying material, and the material in the safe position A_safe is about to move to the discharge port. The controller controls the previous belt conveyor to start, so that the material is transported from the current belt conveyor to the previous belt conveyor. If not, it indicates that the previous belt conveyor is not carrying material, and the previous belt conveyor does not start. At the same time, the controller controls the current belt conveyor and the started belt conveyor to stop.

[0010] Furthermore, a reader / writer is installed on one side of each level of belt conveyor, and an electronic tag is embedded in each section of the conveyor belt. The electronic tag is used to store the corresponding logical segment number Bx, and the reader / writer is used to read the corresponding logical segment number Bx. An encoder is installed on each level of belt conveyor, and the encoder is used to detect the running speed of the belt conveyor;

[0011] Further, step S2 includes: step S2 includes: S21, when the current belt conveyor is started, the logical segment number is read in real time by the reader / writer to realize the positioning of each logical segment conveyor belt of the belt conveyor, and after positioning, the material flow I carried by the current logical segment conveyor belt corresponding to the fixed position A is collected and stored in real time. X , record the collection time t;

[0012] S22, after the current belt conveyor is started, the running speed V of the conveyor belt is collected in real time through the encoder and the running speed V is sent to the controller;

[0013] S23, calculating the material flow Q[Bx,t] per unit length corresponding to the logical segment number Bx at time t, wherein the material flow Q[Bx,t]=Ix / V, and recording the material flow Q[Bx,t] in the material flow database;

[0014] Furthermore, the material flow rate I X Calculated based on the weight or volume of the material passing through the fixed position A of the current belt conveyor per unit time;

[0015] Furthermore, the time t' is pre-set, and the time t' refers to the time when a specific logical section of the conveyor belt moves to the safe position A_safe after the belt conveyor is started;

[0016] The fixed position A refers to any spatial position pre-set in each level of belt conveyor;

[0017] Furthermore, step S4 also includes determining whether the material at the safety position A_safe in the current belt conveyor is fully loaded, and the specific determination steps include: A1, presetting a full load operation threshold T in the controller;

[0018] A2. Compare the retrieved material flow Q[Bx',t] at the safe position A_safe with the full-load operation threshold T. If the material flow Q[Bx',t] of x on the current belt conveyor is less than T, it indicates that it is not fully loaded. The drive power of the previous belt conveyor is automatically adjusted proportionally according to the current material flow Q[Bx',t]. If the material flow Q[Bx',t] of x on the current belt conveyor is greater than or equal to T, it indicates that the current belt conveyor is fully loaded. The controller controls the previous belt conveyor to continue running at speed V.

[0019] Furthermore, in step A2, the specific method of automatically adjusting the driving power of the previous belt conveyor in proportion to the current material flow Q[Bx',t] is as follows: calculating the operating ratio k of the conveyor belt in the belt conveyor, k=Q[Bx',t] / T, adjusting the operating speed V1 of the previous belt conveyor to the operating speed V2 according to the ratio k, operating speed V2=k*V1, and when the previous belt conveyor is not fully loaded, the controller controls the previous belt conveyor to start and run at the operating speed V2;

[0020] Furthermore, in step S4, if the material flow Q[Bx',t] of the safety position A_safe of the current-level belt conveyor continues to be 0, and the material flow of the safety position A_safe of the next-level belt conveyor is also 0, indicating that there is no material transportation, the previous-level belt conveyor is not turned on, and the controller controls the current-level belt conveyor and the belt conveyor behind it to stop.

[0021] The above method of the present invention can achieve the following beneficial effects: In the belt conveyor control method based on material flow monitoring of the present application, whether to control the start of the previous belt conveyor is determined according to the material flow at the fixed position of the current belt conveyor. Only when the conveyor belt of the current conveyor carries a certain amount of material, the controller will control the start of the previous belt conveyor, thereby reducing the idling time of the previous belt conveyor, avoiding the problem that there is no material on the belt conveyor, but the belt conveyors at all levels are still started in sequence and continue to idle, which is beneficial to saving energy consumption and reducing belt conveyor wear. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a structural diagram of an existing belt conveyor material transportation system;

[0023] Figure 2 It is a structural schematic diagram of the belt conveyor material transportation system of the present invention;

[0024] Figure 3 This is a schematic diagram of the main structure of the material flow monitoring system of the present invention installed in the belt conveyor material transportation system;

[0025] Figure 4 It is a schematic diagram of the material distribution structure on the belt conveyor of the present invention. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above drawings are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or equipment.

[0027] Figure 1This is a structural diagram of a currently commonly used belt conveyor material transportation system. The belt conveyor includes a first-level belt conveyor (corresponding to number 1), a second-level belt conveyor (corresponding to number 2), a third-level belt conveyor (corresponding to number 3), and a fourth-level belt conveyor (corresponding to number 4). The fourth-level belt conveyor, the third-level belt conveyor, the second-level belt conveyor, and the first-level belt conveyor are started in sequence. After all the belt conveyors are moved, the feed port is opened to unload materials to the fourth-level belt conveyor. The materials are transported to the previous-level belt conveyor in sequence by the fourth-level belt conveyor. Using this method, before the materials are transported forward to the previous-level belt conveyor, the previous-level belt conveyor is in an idling state. The conveying lines at actual production sites are often several kilometers to tens of kilometers long. If the belt conveyor idles for a long time, it will lead to increased equipment wear and waste of electricity.

[0028] In response to the problem in the prior art that multi-stage connected belt conveyors have a long idling time at startup, which easily leads to increased equipment wear and waste of electricity, the present invention provides a specific embodiment of belt conveyor control based on material flow monitoring. Several belt conveyors are connected end to end to form a conveying system. In this embodiment, the conveying system includes a first-stage belt conveyor (corresponding to number 1), a second-stage belt conveyor (corresponding to number 2), a third-stage belt conveyor (corresponding to number 3), and a fourth-stage belt conveyor (corresponding to number 4) connected in sequence. The conveyor belts of each stage of the belt conveyor are respectively driven by a driving device. In this embodiment, the driving device is a servo motor.

[0029] Flow detection devices are installed above the first-level belt conveyor, the second-level belt conveyor, the third-level belt conveyor, and the fourth-level belt conveyor, respectively. The flow detection devices include flow sensors. The flow sensors above the conveyor belts at each level are numbered 11, 21, 31, and 41, respectively. The flow sensors are used to detect the material flow at fixed positions of the conveyor belts at each level. The detection of material flow in this application can also be achieved by using a flow detection device based on machine vision, a flow detection device based on a belt scale, or other existing material flow detection devices and methods. In this embodiment, the numerical value of the material flow represents the weight or volume of the material passing through the fixed position A (i.e., the fixed position) of the current belt conveyor per unit time.

[0030] In this embodiment, the servo motor, flow sensor, reader / writer, and encoder are all electrically connected to the controller. The controller controls the previous-level driving device to drive the previous-level belt conveyor to start according to the material flow carried by the conveyor belt in the current-level belt conveyor logic segment. That is, the controller controls the N-level belt conveyor, the N-1-level belt conveyor...the first-level belt conveyor to start one level at a time.

[0031] The belt conveyor is controlled based on the material flow collected by the above-mentioned flow detection device. Before control, first, due to the large size of the belt conveyor and the long running distance, the conveyor belts of the belt conveyors at each level are divided to facilitate the collection of material flow. S1. The conveyor belts of the belt conveyors at each level are divided into several sections, each of which is represented by a logical segment number Bx arranged in sequence. The logical segment numbers Bx are B1, B2...Bn, and n is a positive integer. A safe position A_safe and a fixed position A are pre-set in the belt conveyors at each level. The safe position A_safe is located near the discharge port of the belt conveyors at each level. The fixed position A refers to an arbitrary spatial position pre-set in the belt conveyors at each level. In this embodiment, the conveyor belts of the belt conveyors at each level are divided into: the first logical segment (represented by B1), the second logical segment (represented by B2), the third logical segment (represented by B3)...the nth logical segment (represented by Bn).

[0032] S2. Establish a material flow database. Specifically: when the conveyor belt of the current belt conveyor rotates at least one circle under the drive of the servo motor, during the rotation, at the fixed position A, each section of the conveyor belt in the current belt conveyor is positioned in turn, and the current time t is recorded. The material flow carried by each section of the conveyor belt corresponding to the fixed position A is collected in turn, recorded as Q[Bx,t], and included in the material flow database.

[0033] Before establishing the material flow database, first set up readers and flow sensors at fixed positions A of each level of belt conveyor, embed electronic tags in each section of conveyor belt, the electronic tags are used to store the corresponding logical segment number Bx, and the readers are used to read the corresponding logical segment number Bx. Encoders are installed on each level of belt conveyor to detect the running speed of the belt conveyor; in this embodiment, the readers are installed at Figure 2 They are represented by 12, 22, 32 and 42 respectively.

[0034] The specific steps of establishing the material flow database include: S21, when the current belt conveyor is started, the corresponding reader and encoder are started synchronously, and the logical segment number is read in real time by the reader to realize the positioning of each logical segment conveyor belt of the belt conveyor. After positioning, the time t is recorded. At the same time, the flow sensor collects the material flow I carried by the current logical segment conveyor belt corresponding to the fixed position A in real time. X And store; material flow I X It is calculated based on the weight or volume of the material passing through the fixed position A of the current belt conveyor per unit time.

[0035] S22, after the belt conveyor is started, the running speed V of the conveyor belt is collected in real time through the encoder and the running speed V is sent to the controller;

[0036] S23. Calculate the material flow Q[Bx,t] per unit length loaded corresponding to the logical segment number Bx at time t, wherein the material flow Q[Bx,t]=Ix / V, and enter the material flow Q[Bx,t] into the material flow database.

[0037] S3. During the operation of the current-level belt conveyor, at a certain moment t', the logical segment conveyor belt passing through the safe position A_safe is located, and the logical segment number Bx' of the logical segment conveyor belt is obtained. Based on the established material flow database, the latest data record Q[Bx',t'] of the conveyor belt logical segment Bx' is retrieved, and Q[Bx',t']=Q[Bx',t]. Therefore, the material flow carried by the conveyor belt corresponding to the safe position A_safe of the current-level belt conveyor is Q[Bx',t].

[0038] Since the safe position A_safe is located behind the fixed position A, the logical segment conveyor belt moves from the fixed position A. When the logical segment conveyor belt passes the fixed position A, the time is t. According to step S2, the system will record and store the material quantity Q[Bx',t] of the logical segment conveyor belt at the time t and store it in the material flow database (that is, the latest data record Q[Bx',t'] of the conveyor belt logical segment Bx'). From the time t to the time t', the material on the conveyor belt with the logical segment number Bx' and the conveyor belt remain relatively stationary. Therefore, at the time t', the material flow Q[Bx',t'] on the conveyor belt logical segment passing the fixed position A_safe is equal to Q[Bx',t], recorded as Q[A_safe, t'].

[0039] The time t' is preset. In this embodiment, the time t' refers to Figure 4 The figure shows the moment when the conveyor belt of the logical segment with the logical segment number B10 moves to the safe position A_safe.

[0040] S4. Determine whether the material flow Q[A_safe, t'] of the current belt conveyor is greater than zero. If so, it indicates that the current belt conveyor is carrying material, and the material in the safe position A_safe is about to move to the discharge port. The controller controls the previous belt conveyor to start, so that the material is transported from the current belt conveyor to the previous belt conveyor. If not, it indicates that the previous belt conveyor is not carrying material, and the previous belt conveyor does not start. At the same time, the controller controls the current belt conveyor and the started belt conveyor to stop.

[0041] In this step, in order to further save energy consumption, while judging whether the material flow Q[A_safe, t'] of the current belt conveyor is greater than zero, it is also judged whether the material in the safe position A_safe in the current belt conveyor is fully loaded, so as to flexibly control the running speed of the previous belt conveyor. The specific steps of judging whether the current conveyor is fully loaded include: A1, pre-setting the full load operation threshold T in the controller;

[0042] A2. Compare the retrieved material flow Q[A_safe, t'] at the safe position A_safe with the full load threshold T:

[0043] If the material flow rate Q[A_safe, t'] of x of the current belt conveyor is less than T, it indicates that it is not fully loaded. The driving power of the previous belt conveyor is automatically adjusted proportionally according to the current material flow rate Q[A_safe, t']. The specific method of automatically adjusting the driving power of the previous belt conveyor proportionally according to the current material flow rate Q[A_safe, t'] is as follows: calculate the operating ratio k of the conveyor belt in the belt conveyor, k=Q[A_safe, t'] / T, and adjust the operating speed V1 of the previous belt conveyor to the operating speed V2 according to the proportion k, and the operating speed V2=K*V1. When the current belt conveyor is not fully loaded, the controller controls the previous belt conveyor to start and run at the operating speed V2.

[0044] If the material flow rate x of the current belt conveyor is Q[A_safe, t'] ≥ T, it indicates that the current belt conveyor is fully loaded, and the controller controls the previous belt conveyor to continue running at speed V.

[0045] In this embodiment, to further improve the accuracy of determining whether the belt conveyor is carrying material flow Q[A_safe, t'], in the above step S4, not only is a judgment made on whether the material flow Q[A_safe, t'] at the safe position A_safe of the current belt conveyor continuously zero, but also a judgment is made on whether the material flow at the safe position A_safe of the subsequent belt conveyor is also zero. If both are zero, indicating no material is being conveyed, the previous belt conveyor is not started, and the controller controls the current belt conveyor and the belt conveyor behind it to stop. If no material is being conveyed, the controller controls the previous belt conveyor to stop, thereby further reducing equipment wear and energy waste.

[0046] The above are only preferred embodiments of the present application, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations directly derived or imagined by those skilled in the art without departing from the spirit and concept of the invention should be considered to be included in the scope of protection of the invention.

Claims

1. A belt conveyor control method based on material flow monitoring, which is used to control the belt conveyors of each level to start in sequence from back to front, and a plurality of belt conveyors are connected end to end to form a conveying system, characterized in that: The method comprises the following steps: S1. Divide the conveyor belts of each belt conveyor into several segments. Each segment is represented by a sequentially arranged logical segment number Bx, B1, B2, ..., Bn, where n is a positive integer. Preset a safe position A_safe and a fixed position A on each belt conveyor. The safe position A_safe is located near the discharge port of each belt conveyor. The fixed position A is the material flow collection location. S2. Position each conveyor belt segment sequentially at a fixed position A in the current belt conveyor, record the time t corresponding to the positioning, and obtain the logical segment number Bx. At the same time, collect the material flow rate per unit length of the conveyor belt segment corresponding to the fixed position A at the time t, record it as Q[Bx,t], and store it in the material flow database; S3. During the operation of the current belt conveyor, at a certain time t', locate the logical segment of the conveyor belt that passes through the safe position A_safe, obtain the logical segment number Bx' of the logical segment of the conveyor belt, and retrieve the latest data record Q[Bx',t] of the conveyor belt logical segment Bx' based on the established material flow database. Therefore, the material flow rate per unit length of the conveyor belt corresponding to the safe position A_safe of the current belt conveyor is Q[Bx',t]. S4. Determine whether Q[Bx',t] is greater than zero. If so, it indicates that the current belt conveyor is carrying material, and the material in the safe position A_safe is about to move to the discharge port. The controller controls the previous belt conveyor to start, so that the material is conveyed from the current belt conveyor to the previous belt conveyor. If not, it indicates that the previous belt conveyor is not carrying material, and the previous belt conveyor does not start. At the same time, the controller controls the current belt conveyor and the already started belt conveyor to stop. Step S4 also includes determining whether the material at the safety position A_safe in the current belt conveyor is fully loaded. The specific determination steps include: A1, presetting a full load operation threshold T in the controller; A2. The material flow rate per unit length of the conveyor belt corresponding to the safe position A_safe of the current belt conveyor is Q[Bx',t]. The Q[Bx',t] is compared with the full-load operation threshold T. If the Q[Bx',t] is less than T, it indicates that it is not fully loaded. The driving power of the previous belt conveyor is automatically adjusted proportionally according to the Q[Bx',t]. If the Q[Bx',t] is greater than or equal to T, it indicates that the current belt conveyor is fully loaded. The controller controls the previous belt conveyor to continue running at the speed V.

2. The belt conveyor control method based on material flow monitoring according to claim 1, characterized in that: A reader / writer is set on one side of each level of belt conveyor, and an electronic tag is embedded in each section of the conveyor belt. The electronic tag is used to store the logical segment number Bx of the corresponding conveyor belt, and the reader / writer is used to read the corresponding logical segment number Bx. Encoders are installed on each level of belt conveyor, and the encoders are used to detect the running speed of the belt conveyor.

3. The belt conveyor control method based on material flow monitoring according to claim 2 is characterized in that: Step S2 includes: S21, when the current belt conveyor is started, the logical segment number is read in real time by the reader / writer to realize the positioning of each logical segment conveyor belt of the belt conveyor, and after positioning, the material flow I carried by the current logical segment conveyor belt corresponding to the fixed position A is collected and stored in real time. X , record the collection time t; S22, after the current belt conveyor is started, the running speed V of the conveyor belt is collected in real time through the encoder and the running speed V is sent to the controller; S23, calculate the material flow Q[Bx,t] per unit length loaded corresponding to the logical segment number Bx at time t, wherein the material flow Q[Bx,t]=Ix / V, and enter the material flow Q[Bx,t] into the material flow database.

4. The belt conveyor control method based on material flow monitoring according to claim 2 or 3, characterized in that: The material flow rate I X It is calculated based on the weight or volume of the material carried by the current logical segment conveyor belt corresponding to the fixed position A of the current level belt conveyor.

5. The belt conveyor control method based on material flow monitoring according to claim 1, characterized in that: The time t' is pre-set, and the time t' refers to the moment when a specific logical section of the conveyor belt moves to the safe position A_safe after the belt conveyor is started. The fixed position A refers to an arbitrary spatial position pre-set in each level of the belt conveyor, and the flow sensor for material flow collection is installed at the fixed position A.

6. The belt conveyor control method based on material flow monitoring according to claim 5, characterized in that: In step A2, the specific method of automatically adjusting the driving power of the previous belt conveyor in proportion to Q[Bx',t] is as follows: calculating the operating ratio k of the conveyor belt in the belt conveyor, k= Q[Bx',t] / T, adjusting the operating speed V1 of the previous belt conveyor to the operating speed V2 according to the ratio k, the operating speed V2=k*V1, and when the previous belt conveyor is not fully loaded, the controller controls the previous belt conveyor to start and run at the operating speed V2.

7. The belt conveyor control method based on material flow monitoring according to claim 1, characterized in that: In step S4, if Q[Bx',t] is continuously 0 and the material flow rate of the safety position A_safe of the subsequent belt conveyor is also 0, indicating that there is no material conveying, the previous belt conveyor is not turned on, and the controller controls the current belt conveyor and the belt conveyor behind it to stop.

Images