Coal blending device and coal blending system

Abstract

The invention provides a coal blending device and a coal blending system. The coal blending device comprises a material transferring unit, a coal unloading groove and a frequency conversion belt scale control unit, and the coal unloading groove is formed in the lower side of the material transferring unit and can receive raw material coal from the material transferring unit; the variable-frequency belt scale control unit comprises a variable-frequency belt scale, a weighing section and a control unit, and under the condition that the real-time height of the raw material coal in the coal unloading groove is not lower than a first preset threshold value and not higher than a second preset threshold value, the control unit can obtain the weighing value of the weighing section at the current moment; the difference value between the weighing value of the current moment of the weighing section and the set value can be determined, and when the difference value is larger than the preset difference value, the rotating speed of the frequency conversion belt weigher can be adjusted based on the feedback signal of the difference value so as to change the discharging speed of the discharging opening of the coal unloading groove. Therefore, the absolute value of the difference value between the weighing value of the weighing section at the next moment and the set value is reduced. Therefore, the coal blending precision of the coal blending device is high, and the coal blending device can be matched with terminal requirements.

Description

Technical Field

[0001] The present application relates to the technical field of coking coal blending, and in particular, to a coal blending device and a coal blending system. Background Art

[0002] Coal blending is the process of mixing different types of coal in a certain proportion to form commercial coal. The commercial coal obtained through coal blending has improved coal quality, high coal utilization rate, and can achieve efficient utilization of non-renewable resources, meeting the needs of different users for commercial coal (terminal coal).

[0003] In the prior art, the coal blending device is usually composed of a control system and multiple coal blending units, wherein the control system can be connected to the multiple coal blending units in communication, each coal blending unit includes a ring-type coal feeder and a fixed-frequency belt scale, and each coal blending unit weighs a type of coal. Before coal blending, it is necessary to first set the standard drop amount of the belt scale of each coal blending unit on the control system according to the respective proportions of each type of coal. During the coal blending operation, the error signal of the actual weighing weight on the belt of each fixed-frequency belt scale and the standard drop amount is applied to the corresponding coal plow truck and coal unloading truck of the ring-type coal feeder, so that the corresponding coal plow truck and coal unloading truck can automatically adjust their own operating speed by frequency conversion, so as to adjust the real-time coal drop amount of each coal blending unit during coal blending, thereby ensuring that multiple types of coal can be blended in the set manner as much as possible.

[0004] However, with the continuous improvement of product process quality requirements, the error signal of the actual weighing weight and the standard dropping amount of the fixed-frequency belt scale is directly applied to the coal blending adjustment method of the coal plow car and the coal unloading car of the ring coal feeder. Due to the large and bulky equipment of the coal plow car and the coal unloading car themselves, as well as the delay caused by the frequency conversion adjustment of the coal plow car and the coal unloading car, in the coking coal blending process, the error between the real-time coal blending amount and the standard dropping amount of a single coal type is large, which affects the quality of the commercial coal and does not match the terminal requirements. Summary of the invention

[0005] Therefore, the purpose of the present application is to provide a coal blending device and a coal blending system to solve the problem in the prior art that due to the large and bulky equipment of the coal plow cars and coal unloading cars themselves, as well as the delay caused by the frequency conversion adjustment of the coal plow cars and coal unloading cars, during the coking coal blending process, the error between the real-time coal blending amount and the standard coal blending amount of a single type of coal is large, thereby affecting the quality of the commercial coal and the mismatch with the terminal requirements.

[0006] According to a first aspect of the present application, a coal blending device is provided, wherein the coal blending device comprises a material transfer unit, a coal discharge chute and a variable frequency belt scale control unit, wherein the coal discharge chute is arranged at the lower side of the material transfer unit and can receive raw coal from the material transfer unit; the variable frequency belt scale control unit comprises a variable frequency belt scale, a weighing section and a control unit, wherein the weighing section is fixedly arranged at one end in the length direction of the variable frequency belt scale and can weigh the weight on the variable frequency belt scale, the discharge port of the coal discharge chute is located above the other end in the length direction of the variable frequency belt scale and can transport raw coal to the variable frequency belt scale, and the control unit is respectively connected to The variable frequency belt scale, the weighing section and the coal unloading chute are communicatively connected. When it is determined that the real-time height of the raw coal in the coal unloading chute is not lower than a first preset threshold value and not higher than a second preset threshold value, the control unit can obtain the weighing value of the weighing section at the current moment, and can determine the difference between the weighing value at the current moment and the set value of the weighing section, and can adjust the rotation speed of the variable frequency belt scale based on the feedback signal of the difference when the difference is greater than the preset difference, so as to change the discharge speed of the discharge port of the coal unloading chute, thereby reducing the absolute value of the difference between the weighing value of the weighing section at the next moment and the set value.

[0007] In some embodiments, the feedback signal based on the difference adjusts the rotation speed of the variable frequency belt scale to change the discharge speed of the coal unloading chute, including: when the weighing value at the current moment is greater than the set value of the weighing section, reducing the rotation speed of the variable frequency belt scale to reduce the discharge speed of the coal unloading chute; or when the weighing value at the current moment is less than the set value of the weighing section, increasing the rotation speed of the variable frequency belt scale to increase the discharge speed of the coal unloading chute.

[0008] In some embodiments, the control unit is communicatively connected with the material transfer unit and is capable of adjusting the material transfer speed of the material transfer unit, thereby controlling the real-time height of the raw coal in the coal unloading chute to be within a range not lower than a first preset threshold and not higher than a second preset threshold.

[0009] In some embodiments, when the real-time height of the raw coal in the coal unloading chute approaches a first preset threshold value and is maintained for a preset time, the control unit can control the material transfer speed of the material transfer unit to increase, and when the real-time height of the raw coal in the coal unloading chute approaches a second preset threshold value and is maintained for a preset time, the control unit can control the material transfer speed of the material transfer unit to decrease.

[0010] In some embodiments, a level meter is provided on the coal unloading chute, and the control unit communicates with the level meter, thereby enabling the control unit to be communicatively connected with the coal unloading chute.

[0011] In some embodiments, the control unit can dynamically adjust the material transfer speed of the material transfer unit based on the feedback signal of the difference and the feedback signal of the material level meter.

[0012] In some embodiments, the coal blending device includes a coal bin, in which raw coal is stored, and the material transfer unit includes a coal plow car, a coal unloading car and a discharger. The coal plow car is provided with at least one coal plow claw, and the coal plow claw can pull raw coal from the bottom of the coal bin; the coal unloading car is provided with a discharge tray, and the discharge tray can receive the raw coal from the coal plow claw; the discharger is arranged above the discharge tray, and when the discharge tray rotates, the discharger can guide the raw coal on the discharge tray to the coal unloading chute.

[0013] In some embodiments, when it is determined that the real-time height of the raw coal in the coal unloading chute is lower than a first preset threshold, the control unit can control the variable frequency belt scale to stop, and can adjust the material transfer speed of the material transfer unit so that the real-time height of the raw coal in the coal unloading chute is within a range not lower than the first preset threshold and not higher than the second preset threshold.

[0014] In some embodiments, when it is determined that the real-time height of the raw coal in the coal unloading chute is higher than a second preset threshold, the control unit can control the material transfer unit to stop.

[0015] In some embodiments, when it is determined that the real-time height of the raw coal in the coal unloading chute is not lower than a first preset threshold and not higher than a second preset threshold, the control unit can control the variable frequency belt scale and the material transfer unit to operate simultaneously.

[0016] According to a second aspect of the present application, a coal blending system is provided, wherein the coal blending system comprises a central control device and a plurality of coal blending devices provided in the above-mentioned embodiments, wherein the central control device is communicatively connected to each coal blending device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The above and / or other features and aspects of the present invention will become clear and easily understood through the description of the embodiments in conjunction with the accompanying drawings.

[0018] Figure 1 A schematic structural diagram of a coal blending device provided according to an embodiment of the present application is shown;

[0019] Figure 2 A schematic diagram of the structure of a coal unloading chute and a variable frequency belt scale of a coal blending device provided according to an embodiment of the present application is shown;

[0020] Figure 3 A flow chart of a control method of a control unit of a coal blending device provided in accordance with an embodiment of the present application is shown.

[0021] Explanation of symbols

[0022] 10. Coal bunker; 20. Material transfer unit; 21. Coal plow car; 22. Coal unloading car; 30. Coal unloading chute; 31. Material discharge port; 41. Weighing section; 42. Frequency conversion belt scale; 50. Unloader. DETAILED DESCRIPTION

[0023] The following specific embodiments are provided to help the reader obtain a comprehensive understanding of the methods, devices and / or systems described herein. However, after understanding the disclosure of the present application, various changes, modifications and equivalents of the methods, devices and / or systems described herein will be clear. For example, the order of operations described herein is only an example and is not limited to those orders set forth herein, but can be changed as will be clear after understanding the disclosure of the present application, except for operations that must occur in a specific order. In addition, for greater clarity and simplicity, the description of features known in the art may be omitted.

[0024] The features described herein can be implemented in different forms and should not be construed as being limited to the examples described herein. Rather, the examples described herein have been provided to illustrate only some of the many possible ways to implement the methods, devices, and / or systems described herein, which will be clear after understanding the disclosure of the present application.

[0025] As used herein, the term "and / or" includes any one of the associated listed items and any combination of any two or more.

[0026] Although terms such as "first", "second", and "third" may be used herein to describe various members, components, regions, layers, or portions, these members, components, regions, layers, or portions should not be limited by these terms. Instead, these terms are only used to distinguish one member, component, region, layer, or portion from another member, component, region, layer, or portion. Therefore, without departing from the teachings of the examples described herein, the first member, first component, first region, first layer, or first portion referred to in the examples may also be referred to as the second member, second component, second region, second layer, or second portion.

[0027] In the specification, when an element such as a layer, a region or a substrate is described as being "on", "connected to" or "mounted to" another element, the element may be directly "on", "connected to" or "mounted to" another element, or one or more other elements may be present therebetween. Conversely, when an element is described as being "directly on", "directly connected to" or "directly mounted to" another element, there may be no other elements therebetween.

[0028] The terms used herein are only used to describe various examples and are not intended to limit the present application. Unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. The terms "comprise", "include" and "have" indicate the presence of the described features, quantities, operations, components, elements and / or combinations thereof, but do not exclude the presence or addition of one or more other features, quantities, operations, components, elements and / or combinations thereof. The term "plurality" represents any number of two and more than two.

[0029] The limitations of directional words such as "above", "below", "front", and "rear" in this application are all based on the reference position of the coal blending device in normal use. This definition method will help ensure that readers or users can clearly understand the relative position relationship of various components and functions, and should not be understood as a limitation of this application.

[0030] Unless otherwise defined, all terms used herein, including technical terms and scientific terms, have the same meaning as those generally understood by a person skilled in the art to which the present application belongs after understanding the present application. Unless explicitly defined as such herein, terms such as those defined in a general dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant field and the present application, and should not be interpreted in an idealized or overly formal manner.

[0031] Furthermore, in the description of the examples, when it is considered that a detailed description of well-known related components or functions will cause vague interpretation of the present application, such detailed description will be omitted.

[0032] Coal blending is the process of mixing different types of coal in a certain proportion to form commercial coal. The commercial coal obtained through coal blending has improved coal quality, high coal utilization rate, and can achieve efficient utilization of non-renewable resources, meeting the needs of different users for commercial coal (terminal coal).

[0033] The following will be combined Figures 1 to 3 The coal blending device provided in the embodiment of the present application is introduced, wherein the coal blending device is applied to a corresponding type of coal, that is, each type of coal is equipped with an independent coal blending device. As an example, the types of coal that form commercial coal include types A, B and C. During the coal blending process, each of types A, B and C corresponds to a coal blending device. In this way, the various types of coal do not interfere with each other during the weighing process, which facilitates the control of the coal blending amount of a single type of coal.

[0034] According to the present application, the coal blending device can ensure that the amount of coal blending is closer to the set value. When the amount of coal blending of each type of coal is closer to the set value, the commercial coal can be made in the expected proportion, thereby ensuring that the quality of the commercial coal matches the terminal requirements. In addition, since the coal blending device continuously adjusts the next moment based on each current moment, the continuous stability of the amount of coal blending during the coal blending process can be ensured, thereby ensuring the stability of the quality of the commercial coal and avoiding the problem of uneven quality caused by local poor quality.

[0035] It should be noted that multiple coal blending devices may share the same control unit, or may each have a corresponding control unit. When multiple coal blending devices have corresponding control units, the multiple control units are connected to the central control system so as to be able to communicate with each other.

[0036] According to an embodiment of the present application, a coal blending device is provided, wherein: Figure 1 to Figure 2 As shown, the coal blending device includes a material transfer unit 20, a coal discharge chute 30, and a variable frequency belt scale control unit. The coal discharge chute 30 is arranged at the lower side of the material transfer unit 20, and can receive the raw coal from the material transfer unit 20. The variable frequency belt scale control unit includes a variable frequency belt scale 42, a weighing section 41, and a control unit. The weighing section 41 is fixedly arranged at one end of the variable frequency belt scale 42 in the length direction, and can weigh the weight of the raw coal on the variable frequency belt scale 42. More specifically, it can weigh the weight of the raw coal on the variable frequency belt scale 42 located on the weighing section. The discharge port 31 of the coal discharge chute 30 is located above the other end of the variable frequency belt scale 42 in the length direction, and can transport the raw coal in the direction where the variable frequency belt scale 42 is located. The control unit is respectively connected to the variable frequency belt scale 42, the weighing section 41, and the coal discharge chute 30 for communication. When the real-time height of the raw coal in the coal discharge chute 30 is not lower than the first preset threshold value and not higher than the second preset threshold value, as shown in FIG. Figure 3 As shown, the control unit can perform the following steps:

[0037] Step S101, obtaining the weighing value of the weighing section at the current moment.

[0038] Step S102, determining the difference between the weighing value of the weighing section at the current moment and the set value.

[0039] Step S103, when the difference is greater than the preset difference, the rotation speed of the variable frequency belt scale is adjusted based on the feedback signal of the difference to change the discharge speed of the discharge port of the coal unloading chute, so that the absolute value of the difference between the weighing value and the set value of the weighing section at the next moment is reduced.

[0040] In the embodiment of the present application, the second preset threshold is greater than the first preset threshold. As an example, the first preset threshold is a low point, and the second preset threshold is a high point. Specifically, the first preset threshold may be in the range of 0.5m-1.5m, and the second preset threshold may be in the range of 2.0m-3.0m. The weighing section 41 is configured with a plurality of force sensors, and the weighing section 41 contacts the variable frequency belt scale 42 through the plurality of force sensors and communicates with the control unit.

[0041] According to the coal blending device provided in the embodiment of the present application, the control unit will obtain the real-time height of the raw coal in the coal discharge chute 30 in real time, and compare the determined real-time height of the raw coal in the coal discharge chute 30 with the first preset threshold and the second preset threshold, so as to determine the range of the real-time height of the raw coal in the coal discharge chute 30. When it is determined that the real-time height of the raw coal in the coal discharge chute 30 is not lower than the first preset threshold and not higher than the second preset threshold, the control unit will determine that the current state is within the normal production range. In this state, the control unit will simultaneously send a control signal to the variable frequency belt scale 42 and the material transfer unit 20, so that the control unit can control the variable frequency belt scale 42 and the material transfer unit 20 to operate simultaneously. In other words, in this state, the variable frequency belt scale 42 conveys the raw coal at an appropriate speed, and the material transfer unit 20 transfers the raw coal from the coal bin to the coal discharge chute 30. In this state, the control unit can obtain the weighing value of the weighing section 41 at the current moment and compare it with the set value. If the difference between the weighing value of the weighing section 41 at the current moment and the set value is greater than the preset difference, for example, greater than 1kg-2kg, the control unit will adjust the speed of the variable frequency belt scale 42 according to the feedback signal of the difference between the weighing value of the weighing section at the current moment and the set value, so as to adjust the discharge speed of the discharge port 31 of the coal discharge chute 30, so that the absolute value of the difference between the weighing value of the weighing section 41 at the next moment and the set value is reduced, that is, the weighing value at the next moment is closer to the set value. In this way, the weighing value of a single type of coal at each moment in the coal blending process can be made closer to the set value, so as to ensure that the fluctuation of the coal blending amount of a single type of coal is small, and further ensure that the quality of the commercial coal matches the terminal requirements. In addition, the speed of the variable frequency belt scale 42 and the discharge speed of the discharge port 31 of the coal discharge chute 30 are adjusted simultaneously based on the feedback signal of the difference, so as to achieve the purpose of quickly adjusting to be close to the set value. Moreover, the difference signal between the current weighing value of the weighing section of the variable frequency belt scale and the set value directly acts on the variable frequency belt scale itself, and there is no delay between devices. Therefore, it can further reduce the fluctuation of the coal blending amount of a single type of coal and further improve the quality of commercial coal.

[0042] In addition, it is determined that the real-time height of the raw coal in the coal unloading chute 30 is not lower than the first preset threshold value and not higher than the second preset threshold value, which means that the raw coal in the coal unloading chute 30 is in sufficient supply. In this case, the control unit executes the relevant control logic, which can avoid the impact of the coal supply fluctuation on the coal blending amount of the coal type, thereby further improving the quality of the commercial coal. In addition, the control unit is respectively connected to the material transfer unit 20, the variable frequency belt scale 42, the weighing section 41, and the coal unloading chute 30 in communication, and can realize the automatic control process, so the entire coal blending process does not require too much manual intervention, which can improve production efficiency and automation level.

[0043] According to the present application, the length of the belt of the variable frequency belt scale 42 is usually longer, the weighing section 41 is at one end (rear end) in the length direction of the variable frequency belt scale 42, and the discharge port 31 of the coal unloading chute 30 is at the other end (front end) in the length direction of the variable frequency belt scale 42, wherein one end and the other end have a considerable length, for example, it can be 5m-8m. It can be understood that the weighing section 41 can weigh the raw coal at the rear end of the variable frequency belt scale 42, and the weight at the rear end can represent the final raw coal discharge amount. On the belt scale, through adjustments at multiple times, the final raw coal discharge amount can be made closer to the set value, thereby making the coal blending accuracy higher to meet terminal requirements.

[0044] According to the present application, the variable frequency belt scale 42 has a variable frequency speed regulation unit, which can be steplessly regulated, that is, the speed can be continuously adjusted within a wide range, rather than simply switching on / off or high / low speed. The variable frequency speed regulation unit of the variable frequency belt scale 42 can make the coal blending device's coal blending amount of multiple coal types closer to the corresponding set value during the coal blending process, thereby improving the accuracy and efficiency of coal blending. The speed of the belt of the variable frequency belt scale 42 can affect the discharge speed of the discharge port 31 of the coal unloading chute 30. When the speed of the variable frequency belt scale 42 increases, the moving speed of the raw coal on the belt will also increase accordingly, resulting in an increase in the discharge speed of the discharge port 31 of the coal unloading chute 30. On the contrary, when the speed of the variable frequency belt scale 42 decreases, the moving speed of the raw coal on the belt will slow down, resulting in a decrease in the discharge speed of the discharge port 31 of the coal unloading chute 30.

[0045] According to the present application, the rotation speed of the belt of the variable frequency belt scale 42 can affect the discharge speed of the discharge port 31 of the coal discharge chute 30, that is, there is a linkage mechanism between the variable frequency belt scale 42 and the coal discharge chute 30, so that the change of the belt rotation speed can directly affect the opening of the discharge port, thereby realizing the adjustment of the discharge speed of the discharge port 31.

[0046] In some embodiments, there may be multiple specific structural forms for the linkage mechanism. As some examples, an adjustable baffle or roller may be provided at the discharge port 31 of the coal discharge chute 30. During operation, the speed of the belt of the variable frequency belt scale 42 can directly affect the opening of the discharge port 31, so that the speed of the belt of the variable frequency belt scale 42 can affect the discharge speed of the discharge port 31 of the coal discharge chute 30. Specifically, when the belt speed of the variable frequency belt scale 42 increases, the driving force becomes larger, which increases the opening of the discharge port 31 relative to the previous moment. In this case, the flow area of ​​the raw coal through the discharge port 31 of the coal discharge chute 30 increases, thereby increasing the discharge speed of the discharge port 31 of the coal discharge chute 30; conversely, when the belt speed of the variable frequency belt scale 42 decreases, the driving force becomes smaller, which decreases the opening of the discharge port 31 relative to the previous moment. In this case, the flow area of ​​the raw coal through the discharge port 31 of the coal discharge chute 30 decreases, thereby decreasing the discharge speed of the discharge port 31 of the coal discharge chute 30.

[0047] In some embodiments, adjusting the speed of the variable frequency belt scale 42 based on the feedback signal of the difference to change the discharge speed of the discharge port 31 of the coal discharge chute 30 includes reducing the speed of the variable frequency belt scale 42 to reduce the discharge speed of the discharge port 31 of the coal discharge chute 30 when the weighing value of the weighing section 41 at the current moment is greater than the set value; or increasing the speed of the variable frequency belt scale 42 to increase the discharge speed of the discharge port 31 of the coal discharge chute 30 when the weighing value of the weighing section 41 at the current moment is less than the set value. It should be noted that when the weighing value of the weighing section 41 at the current moment is greater than the set value, it is necessary to reduce the flow rate flowing into the weighing section 41 at the rear end. In order to reduce the flow rate flowing into the weighing section 41, the speed of the variable frequency belt scale 42 can be reduced to reduce the discharge speed of the discharge port 31 of the coal discharge chute 30, so that the weighing value of the weighing section 41 at the next moment is reduced to be closer to the set value. On the contrary, when the weighing value of the weighing section 41 at the current moment is less than the set value, it is necessary to increase the flow rate flowing into the weighing section 41 at the rear end. In order to increase the flow rate flowing into the weighing section 41, the rotation speed of the variable frequency belt scale 42 can be increased to increase the discharge speed of the discharge port 31 of the coal unloading chute 30, so that the weighing value of the weighing section 41 at the next moment increases to be closer to the set value.

[0048] In these embodiments, the control unit automatically adjusts the rotation speed of the variable frequency belt scale 42 based on the above logic, so as to be able to adjust the amount of coal falling at each moment of the operation of the coal blending device, and ensure that the weighing value of the weighing section 41 of the coal blending device is always maintained near the set value, thereby improving the quality of commercial coal (coal blending products), avoiding various problems caused by uneven products, and better meeting terminal needs.

[0049] According to the present application, a level meter is provided on the coal discharge chute 30, and the control unit communicates with the level meter, so that the control unit is connected to the coal discharge chute 30. During the coal blending process, the level meter can measure the height of the raw coal in the coal discharge chute 30 in real time, and transmit the acquired information to the control unit. Based on the feedback information of the level meter, the control unit can control the operating status of related equipment, such as controlling the frequency conversion belt scale 42 and the material transfer unit 20 to run simultaneously, controlling the frequency conversion belt scale 42 or the material transfer unit 20 to stop, etc.

[0050] In some embodiments, the communication between the control unit and the level meter can be achieved through a communication protocol and an interface. As an example, the communication protocol and the interface may include but are not limited to serial communication such as RS-485, analog signal output, digital signal output, etc.

[0051] According to the present application, the control unit can process and analyze the data fed back by the level meter, and make corresponding control decisions according to the preset logic and preset thresholds. In some embodiments, the control unit will compare the real-time height of the raw coal (the data fed back by the level meter) with the preset first preset threshold and the second preset threshold. When the real-time height of the raw coal is not lower than the first preset threshold and not higher than the second preset threshold, the control unit will control the variable frequency belt scale 42 and the material transfer unit 20 to run simultaneously to maintain a stable supply of raw coal in the coal unloading chute 30. If the real-time height of the raw coal exceeds the preset range, the control unit will trigger the abnormal handling mechanism. For example, when the real-time height of the raw coal is lower than the first preset threshold, the control unit will stop the operation of the variable frequency belt scale 42; when the real-time height of the raw coal is higher than the second preset threshold, the control unit will control the material transfer unit 20 to stop running, and the alarm device can be activated to remind the operator to intervene in time to prevent the raw coal from overflowing and avoid unnecessary operation troubles.

[0052] In some embodiments, the material level meter may include a radar material level meter, an ultrasonic material level meter, a weight-type material level meter, etc. The material level meter may be installed on the top or side of the coal discharge chute 30 .

[0053] According to the present application, the control unit is communicatively connected with the material transfer unit 20. Specifically, a sensor is provided on the material transfer unit 20, and the control unit can communicate with the material transfer unit 20 through the sensor, wherein the control unit can adjust the material transfer speed of the material transfer unit 20, so as to facilitate controlling the real-time height of the raw coal in the coal unloading chute 30 to be within a range not lower than the first preset threshold value and not higher than the second preset threshold value. In this way, while determining that the real-time height of the raw coal in the coal unloading chute 30 is neither too high nor too low, it is ensured that the raw coal can be continuously supplied (stable material dropping) during the operation of the variable frequency belt scale, avoiding the final coal blending amount affected by the interruption of the coal unloading chute 30, and improving the accuracy and reliability of the adjustment of the variable frequency belt scale 42, so as to further improve the accuracy of the coal blending of the coal blending device.

[0054] In some embodiments, when the real-time height of the raw coal in the coal discharge chute 30 approaches the first preset threshold value and maintains the preset time, it means that the amount of raw coal in the coal discharge chute 30 begins to decrease. At this time, the continuous operation of the variable frequency belt scale 42 may not be satisfied. In this case, the control unit can control the material transfer speed of the material transfer unit 20 to increase, so that the raw coal enters the coal discharge chute 30 faster, thereby helping to increase the real-time height of the raw coal in the coal discharge chute 30, so that it is maintained within the range of not less than the first preset threshold value and not higher than the second preset threshold value. When the real-time height of the raw coal in the coal discharge chute 30 approaches the second preset threshold value and maintains the preset time, the control unit can control the material transfer speed of the material transfer unit 20 to decrease. In this case, the amount of raw coal entering the coal discharge chute 30 will decrease, thereby helping to reduce the real-time height of the raw coal in the coal discharge chute 30, so that it is maintained within the range of not less than the first preset threshold value and not higher than the second preset threshold value. The control unit controls the material transfer speed of the material transfer unit 20 so that the real-time height of the raw coal is maintained within a range not lower than the first preset threshold and not higher than the second preset threshold, which can ensure the continuous operation of the variable frequency belt scale 42 at the rear end, avoid operating obstacles or failures due to lack of materials, and also avoid the possibility of excessive accumulation and spillage of raw coal, avoid unnecessary operations (for example, requiring operators to clean up), and ensure safety during coal blending (for example, spillage of raw coal may affect the on-site environment and the safety and health of operators). It should be noted that the preset duration according to the embodiment of the present application can be set according to actual conditions. As an example, the preset duration can be 30s-60s.

[0055] In some embodiments, the control unit can dynamically adjust the material transfer speed of the material transfer unit 20 based on the feedback signal of the difference and the feedback signal of the material level meter. The feedback signal of the difference provides information about the difference between the weighing value of the variable frequency belt scale at the current moment and the set value of the weighing section 41, and the relationship between the weighing value at the current moment and the set value of the weighing section 41 can be predicted based on the difference information. The feedback signal of the material level meter provides real-time information about the supply of raw coal in the coal unloading chute 30, and predicts the change trend of the flow rate of raw coal in the future.

[0056] Specifically, the control logic can be implemented by a PID control algorithm. If the difference is greater than the preset difference, the feedback signal of the difference indicates that the discharge speed of the current discharge port 31 needs to be adjusted. If the difference is not greater than the preset difference, the feedback signal of the difference indicates that the discharge speed of the current discharge port 31 does not need to be adjusted. Under the premise that the discharge speed of the current discharge port 31 needs to be adjusted, it is also necessary to judge the feedback signal of the material level meter at the current moment. If the feedback signal of the material level meter is within the range of not less than the first preset threshold and not higher than the second preset threshold, it is determined that the adjustment can be made. Specifically, when the weighing value at the current moment is greater than the set value of the weighing section 41, the speed of the variable frequency belt scale 42 can be reduced to reduce the discharge speed of the discharge port 31 of the coal discharge chute 30. Or when the weighing value at the current moment is less than the set value of the weighing section 41, the speed of the variable frequency belt scale 42 is increased to increase the discharge speed of the discharge port 31 of the coal discharge chute 30. If the feedback signal of the material level meter is below the first preset threshold, the variable frequency belt scale 42 needs to be stopped; if the feedback signal of the material level meter is above the second preset threshold, the material transfer unit 20 needs to be stopped.

[0057] In some embodiments, when it is determined that the real-time height of the raw coal in the coal discharge chute 30 is lower than the first preset threshold, it means that the amount of coal in the coal discharge chute 30 may not be enough to maintain the subsequent production needs. In this case, the control accuracy of the variable frequency belt scale 42 will be affected. In addition, it will cause the equipment to run idle, resulting in energy waste. Therefore, when the control unit determines that the real-time height of the raw coal in the coal discharge chute 30 is lower than the first preset threshold, the control unit can control the variable frequency belt scale 42 to stop, and can adjust the material transfer speed of the material transfer unit 20 so that the real-time height of the raw coal in the coal discharge chute 30 is within the range of not less than the first preset threshold and not higher than the second preset threshold. Then, in this case, the variable frequency belt scale 42 is continued to be controlled to operate, so that the accuracy of the final raw coal drop amount can be further improved to be closer to the set value. At the same time, when the real-time height of the raw coal in the coal discharge chute 30 is higher than the second preset threshold, the control unit can control the material transfer unit 20 to stop. In this way, the problem of excessive accumulation and overflow of raw coal in the coal unloading chute 30 can be avoided, waste and unnecessary additional operations can be avoided, such as cleaning up the overflowed raw coal, and ensuring the safety of the coal blending process (the spillage of raw coal may affect the work site environment and the safety and health of the operator).

[0058] The inventors have found that agglomeration in the coal blending chute can also seriously affect the weighing accuracy of the variable frequency belt scale 42. This is because agglomeration can cause uneven distribution of the raw coal on the belt, making it difficult for the belt scale to accurately capture the actual weight of the raw coal during weighing. In addition, agglomeration can also cause vibration or instability of the belt scale, further reducing the weighing accuracy.

[0059] The particle size of the raw coal is generally in the range of several millimeters to more than ten centimeters. Since the size of the raw coal is smaller than that of the finished coal, it may clump during the batching process, especially when the coal unloading chute 30 is designed as an inverted cone structure. Although this structure helps to concentrate and flow the raw coal, it may also aggravate the formation of lumps because smaller particles are easy to squeeze and stick to each other in the cone area.

[0060] Therefore, making the raw coal as dispersed as possible at the front end of the coal blending chute will help lay the foundation for subsequent weighing accuracy.

[0061] In some embodiments, the coal blending device includes a coal bunker in which raw coal is stored. The material transfer unit 20 includes a coal plow car 21 and a coal unloading car 22. The coal plow car 21 is provided with at least one coal plow claw, which can pull raw coal from the bottom of the coal bunker. The coal unloading car 22 is provided with a discharge tray, which can receive the raw coal from the coal plow claw, and the raw coal can be transported to the coal unloading chute 30.

[0062] In these embodiments, a coal plowing claw is provided on the coal plowing car 21. When the coal plowing car 21 is running, the coal plowing claw will move according to the set trajectory and speed, and can effectively pick up the raw coal at the bottom of the coal bunker and transport the raw coal to the subsequent material transfer unit. In addition to picking up the raw coal, the coal plowing claw will also have a certain disturbance effect on the raw coal in the coal bunker during the movement, thereby helping to break up the agglomeration or compaction layer that may exist in the coal bunker, so that the raw coal can be evenly distributed in the form of particles, reducing the occurrence of coal blockage, especially for coal bunkers that have not been used for a long time or coal types with high water content, the loosening effect of the coal plowing claw is particularly obvious. The discharge tray on the coal unloading car 22 can receive the raw coal picked up by the coal plowing claw for temporary storage, so as to facilitate further transportation to the coal unloading chute 30. By cooperating with the coal plowing car 21 and the coal unloading car 22 to transfer materials, the occurrence of loose coal and material interruption can be effectively avoided.

[0063] In some embodiments, the material transfer speed of the coal plow car 21 and the coal unloading car 22 is adjustable in real time, and the control unit is respectively connected to the coal plow car 21 and the coal unloading car 22 in communication, so as to adjust the material transfer speed of the material transfer unit 20. Specifically, the coal plow car 21 and the coal unloading car 22 are both variable frequency adjustable. As an example, the variable frequency adjustable coal plow car 21 and the coal unloading car 22 are controlled by the frequency converter driving motor. The control unit can dynamically adjust the running speed of the coal plow car 21 and the coal unloading car 22 according to the difference signal between the weighing value of the weighing section at the current moment and the set value on the variable frequency belt scale and the signal fed back by the material level meter. Taking the coal plow car 21 as an example, the control logic of the coal blending device is briefly described. Specifically, the control unit can adjust the material transfer speed of the coal plow in real time according to the difference signal between the weighing value of the weighing section at the current moment and the set value on the variable frequency belt scale and the signal fed back by the material level meter, so as to ensure the stability of the raw coal in the unloading chute, meet the requirements of the rear-end variable frequency belt scale during operation, and avoid the error of the coal blending amount caused by the lack of material in the unloading chute. It should be noted that the control logic of the coal unloading vehicle 22 is similar to the above and will not be described in detail here.

[0064] In these embodiments, the material transfer speed of the material transfer unit 20 is controlled by cooperating with the coal plow truck 21 and the coal unloading truck 22 to ensure that the real-time height of the raw coal in the coal unloading chute 30 is maintained within a range not lower than the first preset threshold value and not higher than the second preset threshold value, thereby ensuring that the real-time height of the raw coal in the coal unloading chute 30 is stable and avoiding the accuracy of the coal distribution amount being affected by the lack of material in the coal unloading chute 30.

[0065] In some embodiments, the material transfer unit 20 further includes a discharger 50, which is disposed above the discharge tray. When the discharge tray rotates, the discharger 50 can effectively guide the raw coal from the surface of the discharge tray to the coal discharge chute 30. With the assistance of the discharger 50, the raw coal can be evenly dispersed into the coal discharge chute 30. The assistance of the discharger 50 helps to break the agglomeration formed at the front end and avoid the generation of new agglomerations, which can help to further improve the quality of coal blending and avoid affecting the weighing accuracy due to excessive agglomeration of the raw coal in the coal discharge chute 30.

[0066] Specifically, the material transfer unit 20 includes a ring-type coal feeder, a coal plow car 21 located at the upper part of the ring-type coal feeder, and a coal unloading car 22 located at the lower part of the ring-type coal feeder. The coal plow car 21 is provided with at least one coal plow claw, which can extract raw coal from the bottom of the coal bin and can rotate counterclockwise. The coal unloading car 22 is provided with a discharge tray, which can receive the raw coal from the coal plow claw and rotate clockwise with the rotation of the ring-type coal feeder. The provision of a discharge tray on the coal unloading car 22 can help the uniform distribution and further transportation of the raw coal. When the raw coal on the coal unloading car 22 rotates to the discharge port 31 of the coal unloading chute, the unloader will start to block the raw coal and divert it into the coal unloading chute. The coal unloading chute is directly connected to the variable frequency belt scale. After the raw coal falls from the coal unloading chute into the variable frequency belt scale, the variable frequency belt scale starts to work. The variable frequency belt scale monitors the weight of the raw coal in real time and automatically adjusts its speed according to the difference between the current weighing and the set value, thereby realizing accurate control of the amount of coal falling. In addition, the coal plow car 21 located at the upper part of the ring-type coal feeder and the coal unloading car 22 located at the lower part of the ring-type coal feeder move in opposite directions, which can avoid mutual interference between the two during operation, and can ensure that the raw coal is further dispersed during the material transfer process to a certain extent, ensuring that the raw coal is not easy to agglomerate.

[0067] According to the present application, the material transfer unit 20 can transfer the raw coal from the coal bunker 10 to the coal discharge chute 30. The coal discharge chute 30 is arranged at the lower side of the material transfer unit 20 for receiving and temporarily storing the raw coal from the material transfer unit 20. Here, the coal discharge chute 30 serves as a buffer area for the raw coal, ensuring that the raw coal can enter the weighing section 41 of the variable frequency belt scale 42 for weighing smoothly and orderly. During the coal blending process, when the height of the raw coal in the coal discharge chute 30 is lower than the first preset threshold, at this time, the control unit will first control the variable frequency belt scale 42 to stop working to prevent continued transportation when the amount of coal is insufficient, affecting the precision control of the variable frequency belt scale 42 for weighing. Next, the control unit will adjust the material transfer speed of the material transfer unit 20 to increase the amount of raw coal delivered from the discharge tray to the coal discharge chute 30 to quickly increase the height of the raw coal in the coal discharge chute 30. When it is determined that the real-time height of the raw coal in the coal discharge chute 30 is not lower than the first preset threshold value and not higher than the second preset threshold value, the variable frequency belt scale 42 and the material transfer unit 20 are controlled to run simultaneously, which can ensure the continuous feeding of the subsequent variable frequency belt scale 42, avoid affecting the weighing accuracy due to insufficient raw coal in the coal discharge chute 30 or avoid waste caused by excessive raw coal in the coal discharge chute 30, and through the joint action of the two, improve the accuracy of the final raw coal falling amount. At the same time, the control unit will continue to monitor the height of the raw coal in the coal discharge chute 30 and ensure that it does not exceed the second preset threshold value. And when the height of the raw coal in the coal discharge chute 30 is close to this upper limit, the control unit will correspondingly reduce the material transfer speed of the material transfer unit 20 to avoid the problem of overflow caused by excessive accumulation of raw coal in the coal discharge chute 30.

[0068] According to the present application, when the raw coal in the coal unloading chute is basically stable, a variable frequency belt scale is used as the core control element, which can monitor and adjust the amount of raw coal dropped at each moment in real time, so as to achieve the coal blending amount in line with the actual demand. Taking data as an example, in the prior art, the accuracy of the coal blending method can only reach 10% at most, while the coal blending accuracy according to the present application can reach less than 2%. In addition, the coal at the bottom of the coal bunker is evenly picked up by the coal plow claws on the coal plow car 21, and the raw coal is evenly transported to the designated coal unloading chute with the help of the clockwise rotation of the coal unloading car 22, ensuring the continuous and uniform supply of coal, avoiding the impact of the subsequent control accuracy of the variable frequency belt scale due to material interruption, and effectively avoiding the occurrence of coal interruption. In addition, the entire coal blending process has achieved a high degree of automation and intelligence, greatly reducing the need for manual intervention. This not only reduces labor intensity, but also improves work efficiency and safety.

[0069] According to a second aspect of the present application, a coal blending system is provided, wherein the coal blending system includes a coal blending device provided according to each of the above embodiments, and therefore has all the beneficial effects of the above coal blending device, which will not be described one by one here.

[0070] In some embodiments, the coal blending system includes a central control device and multiple coal blending devices provided according to the above-mentioned embodiments, wherein the central control device is communicatively connected to each coal blending device, and each coal blending device is configured with a type of coal, so that multiple types of coal are blended to form commercial coal.

[0071] Although the embodiments of the present application have been described in detail above, those skilled in the art may make various modifications and variations to the embodiments of the present application without departing from the spirit and scope of the present application. However, it should be understood that, in the opinion of those skilled in the art, these modifications and variations will still fall within the spirit and scope of the embodiments of the present application defined by the claims.

Claims

1. A coal blending device, characterized in that: The coal blending device comprises: A material transfer unit (20); A coal discharge chute (30) is disposed at the lower side of the material transfer unit (20) and is capable of receiving raw coal from the material transfer unit (20); A variable frequency belt scale control unit comprises a variable frequency belt scale (42), a weighing section (41) and a control unit, wherein the weighing section (41) is fixedly arranged at one end of the variable frequency belt scale (42) in the length direction and is capable of weighing the weight on the variable frequency belt scale (42); a discharge port (31) of the coal discharge chute (30) is located above the other end of the variable frequency belt scale (42) in the length direction and is capable of conveying raw coal to the variable frequency belt scale (42); the control unit is respectively connected to the variable frequency belt scale (42), the weighing section (41) and the coal discharge chute (30) for communication; and after determining the coal discharge chute (30), the control unit is connected to the variable frequency belt scale (42), the weighing section (41) and the coal discharge chute (30). When the real-time height of the raw coal in the trough (30) is not lower than a first preset threshold value and not higher than a second preset threshold value, the control unit can obtain the weighing value of the weighing section (41) at the current moment, and can determine the difference between the weighing value of the weighing section (41) at the current moment and the set value, and can adjust the rotation speed of the variable frequency belt scale (42) based on the feedback signal of the difference when the difference is greater than the preset difference, so as to change the discharge speed of the discharge port (31) of the coal unloading trough (30), thereby reducing the absolute value of the difference between the weighing value of the weighing section (41) at the next moment and the set value.

2. The coal blending device according to claim 1, characterized in that: The step of adjusting the rotation speed of the variable frequency belt scale (42) based on the feedback signal of the difference to change the discharge speed of the discharge port (31) of the coal discharge chute (30) comprises: When the weighing value at the current moment is greater than the set value, the rotation speed of the variable frequency belt scale (42) is reduced to reduce the discharge speed of the discharge port (31) of the coal discharge chute (30); or When the weighing value at the current moment is less than the set value, the rotation speed of the variable frequency belt scale (42) is increased to increase the discharge speed of the discharge port (31) of the coal discharge chute (30).

3. The coal blending device according to claim 1, characterized in that: The control unit is in communication connection with the material transfer unit (20) and is capable of adjusting the material transfer speed of the material transfer unit (20), thereby controlling the real-time height of the raw coal in the coal discharge chute (30) to be within a range not lower than a first preset threshold value and not higher than a second preset threshold value.

4. The coal blending device according to claim 3, characterized in that: When the real-time height of the raw coal in the coal unloading chute (30) approaches a first preset threshold value and is maintained for a preset time, the control unit can control the material transfer speed of the material transfer unit (20) to increase; and when the real-time height of the raw coal in the coal unloading chute (30) approaches a second preset threshold value and is maintained for a preset time, the control unit can control the material transfer speed of the material transfer unit (20) to decrease.

5. The coal blending device according to claim 1, characterized in that: The coal unloading chute (30) is provided with a material level meter, and the control unit communicates with the material level meter, so that the control unit is communicatively connected with the coal unloading chute (30).

6. The coal blending device according to claim 5, characterized in that: The control unit can dynamically adjust the material transfer speed of the material transfer unit (20) based on the feedback signal of the difference and the feedback signal of the material level meter.

7. The coal blending device according to claim 3, characterized in that: The coal blending device also includes a coal bunker, in which raw coal is stored. The material transfer unit (20) includes a coal plow car (21), a coal unloading car (22) and a discharger (50). The coal plow car (21) is provided with at least one coal plow claw, which can extract raw coal from the bottom of the coal bunker. The coal unloading car (22) is provided with a discharge tray, which can receive the raw coal from the coal plow claw. The discharger (50) is arranged above the discharge tray. When the discharge tray rotates, the discharger (50) can guide the raw coal on the discharge tray to the coal unloading chute (30).

8. The coal blending device according to claim 1, characterized in that: When it is determined that the real-time height of the raw coal in the coal unloading chute (30) is lower than a first preset threshold value, the control unit can control the variable frequency belt scale (42) to stop, and can adjust the material transfer speed of the material transfer unit (20) so that the real-time height of the raw coal in the coal unloading chute (30) is within a range not lower than the first preset threshold value and not higher than the second preset threshold value.

9. The coal blending device according to claim 1, characterized in that: When it is determined that the real-time height of the raw coal in the coal discharge chute (30) is higher than a second preset threshold, the control unit can control the material transfer unit (20) to stop.

10. The coal blending device according to claim 1, characterized in that: When it is determined that the real-time height of the raw coal in the coal discharge chute (30) is not lower than a first preset threshold value and not higher than a second preset threshold value, the control unit can control the variable frequency belt scale (42) and the material transfer unit (20) to operate simultaneously.

11. A coal blending system, characterized in that: The coal blending system comprises a central control device and a plurality of coal blending devices according to any one of claims 1 to 10, wherein the central control device is communicatively connected to each of the coal blending devices.

Images