An adaptive variable diameter screw conveyor and method of use thereof

Abstract

The present application relates to material conveying technology field, especially to a kind of self-adapting variable-diameter screw conveyor and its using method, including: machine body shell, feed hopper, discharge port, screw shaft, spiral blade, driving motor being set on the upper portion of one end of machine body shell, the diameter of spiral blade gradually reduces from feed end to discharge end;Data acquisition module including fiber material volume acquisition unit, screw shaft sound signal acquisition unit and current acquisition unit;With to determine whether the delivery of self-adapting variable-diameter screw conveyor is up to standard according to fiber material resilience control module;With to determine the speed regulation strategy for driving motor according to peak value proportion difference and to determine the adjustment strategy of self-adapting variable-diameter screw conveyor when delivery is not up to standard according to current fluctuation value correction module.The present application improves the conveying efficiency of screw conveyor.

Description

Technical Field

[0001] This invention relates to the field of material handling technology, and in particular to an adaptive variable diameter screw conveyor and its usage method. Background Technology

[0002] In fields such as agricultural straw recycling and industrial fiber waste treatment, screw conveyors are core equipment for the continuous conveying of fibrous materials, and their conveying efficiency and material processing quality directly affect the stability of the production process.

[0003] A screw conveyor is a type of conveyor without flexible traction components. It moves materials by rotating a shaft with helical blades in a closed trough or by rotating a cylinder with internal helical blades.

[0004] In simple terms, the working principle of a screw conveyor is that, under the pushing action of the screw blades, the material moves upward along the circumference (and collapses downward at a certain position) while simultaneously flowing along the axial direction. During this complex motion, the material is thoroughly mixed due to the shearing action of the blades as they squeeze into the mixture, the throwing action of the mixture under centrifugal force, the shearing action between the flow layers, and the mixing effect of the bidirectional cross-flow of the upper and lower layers.

[0005] A variable diameter screw conveyor is an integrated device that achieves material compression and conveying through a gradient change in the diameter of the screw blades along the axial direction. Its core principle is to apply radial extrusion force to the material during conveying by continuously or segmentally reducing the outer diameter of the blades from the inlet to the outlet, while simultaneously achieving axial transport through screw thrust. The outer diameter of the variable diameter screw is not fixed but changes synchronously with the diameter of the screw blades.

[0006] Fiber materials are a class of loose materials whose main components are plant fibers, synthetic fibers or natural polymer fibers. Their types include agricultural waste (straw, rice husks, bagasse), industrial by-products (textile scraps, wood fibers, pulp) and biomass energy raw materials (energy grass, hemp crops).

[0007] The diameter of the helical blades in a variable diameter screw conveyor is not fixed. This variation allows the conveyor to better adapt to the characteristics of fibrous materials. During the conveying process, the change in the diameter of the helical blades allows for the application of a more suitable driving force to the fibrous material.

[0008] Chinese Patent Application Publication No. CN109502252A discloses an anti-clogging screw conveyor, including a machine body, a power mechanism, a screw conveying mechanism disposed inside the machine body, and a discharge port disposed below the tail of the machine body. A feeding mechanism is disposed above the head of the machine body, and a material stirring device is disposed inside the feeding mechanism. The screw conveying mechanism is installed inside the machine body along the transverse length direction of the machine body. The rotation of the screw conveying mechanism axially propels the material. A second stirring rod is disposed on the screw conveying mechanism directly below the feeding mechanism. The screw conveying mechanism is connected to the power mechanism for transmission.

[0009] It can be seen that the above technical solution does not consider the variable diameter design of the spiral blades, and only uses the stirring rod to help disperse the material. The fibrous material cannot be compressed during the conveying process, which easily leads to blockage. Furthermore, it is necessary to rely on additional anti-blocking structures to passively deal with the blockage, resulting in the low conveying efficiency of the screw conveyor. Summary of the Invention

[0010] Therefore, the present invention provides an adaptive variable diameter screw conveyor and its usage method to overcome the problems of low conveying efficiency of screw conveyors in the prior art, which does not consider the variable diameter design of the screw blades, only relies on the stirring rod to assist in dispersing materials, and the fibrous materials cannot be compressed during the conveying process, are prone to blockage, and need to rely on additional anti-blocking structures to passively deal with blockages.

[0011] To achieve the above objectives, in one aspect, the present invention provides an adaptive variable diameter screw conveyor, comprising:

[0012] The machine body has an outer casing, a feed hopper located at the upper part of one end of the outer casing, and a discharge port located at the lower part of the outer casing at the end away from the feed hopper. A spiral shaft is installed through the interior of the outer casing, and spiral blades are provided on the surface of the spiral shaft. A drive motor is located at the end of the spiral shaft near the feed hopper. The end of the outer casing with the feed hopper is referred to as the feed end, and the end of the outer casing with the discharge port is referred to as the discharge end. The diameter of the spiral blades gradually decreases from the feed end to the discharge end.

[0013] The data acquisition module includes a fiber material volume acquisition unit respectively disposed in the feed hopper and the discharge port, a spiral shaft sound signal acquisition unit disposed in the outer shell of the machine body, and a current acquisition unit disposed in the drive motor.

[0014] The control module, which is connected to the data acquisition module, is used to determine whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the rebound rate of the fiber material at the discharge port; and to make a secondary determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period.

[0015] The correction module is connected to the control module and the drive motor respectively, and is used to determine the speed adjustment strategy for the drive motor based on the peak ratio difference and to determine the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor.

[0016] Furthermore, the control module determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the comparison result of the fiber material rebound rate at the discharge port being greater than or equal to the first preset fiber material rebound rate. When the fiber material rebound rate is greater than or equal to the second preset fiber material rebound rate, the control module further determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the proportion of abnormal sound peak values ​​of the screw shaft within a preset period. The first preset fiber material rebound rate is less than the second preset fiber material rebound rate.

[0017] Furthermore, the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the comparison result that the rebound rate of the fiber material at the discharge port is less than the first preset fiber material rebound rate, and the correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor.

[0018] Furthermore, the process of obtaining the resilience of the fiber material includes:

[0019] A fiber material volume acquisition unit is provided in the feed hopper and the discharge port respectively;

[0020] The first volume of the fiber material in the feed hopper and the second volume of the fiber material after compression at the discharge port are obtained by measurement.

[0021] The compressed volume of the fibrous material is the difference between the first volume of the material and the second volume of the fibrous material;

[0022] After the fiber material is discharged from the outlet and left to stand for a first preset time, the volume of the material after rebound and stabilization is measured and recorded as the third volume.

[0023] The rebound volume of the fiber material is the difference between the third volume and the second volume;

[0024] The resilience rate of the fiber material is the ratio of the rebound volume of the fiber material to the compressed volume of the fiber material.

[0025] Furthermore, the control module makes a secondary determination, based on the percentage of abnormal sound peaks of the screw shaft within a preset period, whether the conveying of the adaptive variable diameter screw conveyor meets a preset standard.

[0026] If the percentage of abnormal sound peaks is less than a preset percentage, then the conveying of the adaptive variable diameter screw conveyor is determined to meet the preset standard.

[0027] If the percentage of abnormal sound peaks is greater than or equal to the preset percentage, it is determined that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard. The control module controls the feeding to stop, and after a second preset time delay, the correction module executes a speed adjustment strategy for the drive motor.

[0028] Furthermore, the percentage of abnormal sound peaks is the ratio between the number of abnormal sound peaks and the total number of sound peaks within a preset period, where abnormal sound peaks are sound peaks that exceed the preset sound peak.

[0029] Furthermore, the process by which the correction module determines the speed adjustment strategy for the drive motor based on the peak percentage difference includes:

[0030] The peak percentage difference is compared with the first preset peak percentage difference and the second preset peak percentage difference, respectively;

[0031] If the peak percentage difference is less than the first preset peak percentage difference, the speed of the drive motor will be reduced to the second preset speed.

[0032] If the peak percentage difference is greater than or equal to the first preset peak percentage difference and less than the second preset peak percentage difference, then the speed of the drive motor is first reduced to zero and maintained at zero speed for a third preset time, then the speed of the drive motor is reversed and the reverse speed is increased to a third preset speed and maintained at the third preset speed for a fourth preset time, then the speed of the drive motor is forward and the forward speed is increased to a fourth preset speed, while the control module controls the resumption of feeding.

[0033] If the peak percentage difference is greater than or equal to the second preset peak percentage difference, the system will stop and an alarm will be issued.

[0034] The peak percentage difference is the difference between the peak percentage of the abnormal sound and the preset percentage.

[0035] Furthermore, the correction module determines an adjustment strategy for when the conveying of the adaptive variable diameter screw conveyor does not meet a preset standard based on the current fluctuation value of the drive motor, wherein...

[0036] If the current fluctuation value is less than the preset current fluctuation value, the amount of fiber material input is reduced according to the difference between the preset current fluctuation value and the current fluctuation value.

[0037] If the current fluctuation value is greater than or equal to the preset current fluctuation value, the machine will stop and an alarm will be issued.

[0038] Furthermore, the current fluctuation value of the drive motor is the absolute value of the difference between the current of the drive motor and the preset current.

[0039] On the other hand, the present invention provides a method of using an adaptive variable diameter screw conveyor, comprising:

[0040] The drive motor is started to the first preset speed, causing the spiral shaft to drive the spiral blades to rotate and feed fiber material into the feed hopper. During the transportation of the fiber material, the data acquisition module collects the sound signal of the spiral shaft during operation and the current of the drive motor. The fiber material is conveyed to the discharge port through the spiral blades. The fiber material volume acquisition unit of the data acquisition module collects the first volume of the fiber material in the feed hopper, the second volume of the fiber material after compression at the discharge port, and the third volume of the fiber material after standing for a first preset time.

[0041] The control module calculates the resilience rate of the fiber material and determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the resilience rate. Then, the control module makes a second determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period. If the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period, the correction module determines the speed adjustment strategy for the drive motor based on the difference in peak percentages.

[0042] When the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the resilience rate of the fiber material, the correction module determines the adjustment strategy for the conveying of the adaptive variable diameter screw conveyor when it does not meet the preset standard based on the current fluctuation value of the drive motor.

[0043] Once the delivery task is completed, the drive motor is stopped.

[0044] Compared with existing technologies, the advantages of this invention lie in its combination of variable-diameter spiral blade structure with multi-dimensional data monitoring, graded intelligent judgment, and dynamic adaptive adjustment. This overcomes the limitations of constant-diameter spiral blades, which have poor compression effect on fiber materials and rely on passive anti-clogging mechanisms. The spiral blade diameter gradually decreases from the inlet to the outlet, forming a natural compression channel. This design allows the fiber material to continuously withstand axially increasing compressive force during conveying, effectively suppressing its rebound potential energy. Simultaneously, the initial judgment of conveying quality is achieved by calculating the fiber material rebound rate, and secondary verification is performed by combining the percentage of abnormal sound peaks, forming a graded judgment logic. This effectively avoids misjudgment based on a single indicator and ensures accurate judgment of the conveying status. The correction module dynamically adjusts the drive motor speed, fiber material input, or activates emergency measures based on the judgment results, achieving fault adaptive handling and thus improving conveying efficiency.

[0045] Furthermore, by designing the spiral blades with a gradually decreasing diameter from the inlet to the outlet, this invention enables gradual compression of the fibrous material during transport, avoiding material agglomeration, entanglement, or fiber structure damage caused by instantaneous compression in constant-diameter spiral blades. This gradual compression method ensures the compactness of the material during transport while reducing the risk of blockage caused by excessive local compression, thereby improving the adaptability of the transport process to the physical properties of the fibrous material.

[0046] Furthermore, the present invention first makes a preliminary judgment based on the rebound rate of the fiber material at the discharge port through the control module. When the rebound rate of the fiber material is greater than or equal to the first preset value, the conveying meets the standard to reduce unnecessary intervention and improve efficiency. When the rebound rate of the fiber material is greater than or equal to the second preset value, the proportion of abnormal sound peak of the screw shaft is introduced for a second judgment. This dual judgment mechanism can more comprehensively and accurately reflect the actual operating status of the conveyor, avoid misjudgment that may be caused by a single judgment basis, and thus improve the reliability of the evaluation.

[0047] Furthermore, this invention sets the resilience rate of fiber materials as a quantitative indicator to measure the compression quality and stability of fiber materials. The control module transforms the abstract compression quality requirements into specific judgment logic by comparing the resilience rate with a preset threshold, achieving accurate decision-making based on objective data. Simultaneously, the dynamic changes in the resilience rate provide feedback for adaptive control. When the resilience rate falls within different ranges, the control module adaptively switches the judgment dimension, thereby improving the adaptability to fiber materials and the controllability of conveying quality.

[0048] Furthermore, this invention uses a correction module to divide the response mechanism into three levels based on the peak percentage difference. In the case of a mild anomaly, the speed of the drive motor is reduced to alleviate local friction and avoid forced conveying that could damage the blades. In the case of a moderate anomaly, a timing adjustment strategy of zero-speed dwell, reverse rotation, and forward recovery is adopted to loosen the blocked material by reversing the flow and output the residual material in the forward direction. In the case of a severe anomaly, the machine is stopped directly and an alarm is issued to prevent equipment damage, thereby improving the reliability of equipment operation.

[0049] Furthermore, the present invention achieves precise control over the reduction in the amount of fiber material input by setting the amount of fiber material input to be reduced based on the difference between the preset current fluctuation value and the current fluctuation value. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the adaptive variable diameter screw conveyor according to an embodiment of the present invention;

[0051] Figure 2 This is a flowchart illustrating how an adaptive variable diameter screw conveyor determines whether the conveying of the fiber material meets a preset standard based on the resilience of the fiber material, according to an embodiment of the present invention.

[0052] Figure 3 This is a flowchart illustrating the adjustment strategy for an adaptive variable diameter screw conveyor when its conveying does not meet a preset standard, as described in an embodiment of the present invention.

[0053] Figure 4 This is a flowchart illustrating the usage method of the adaptive variable diameter screw conveyor according to an embodiment of the present invention;

[0054] In the diagram, 1 is the outer casing of the machine; 2 is the feed hopper; 3 is the discharge port; 4 is the screw shaft; 5 is the screw blades; and 6 is the drive motor. Detailed Implementation

[0055] To make the objectives and advantages of the present invention clearer, the present invention will be further described below with reference to embodiments; it should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0056] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0057] It should be noted that the data in this embodiment are all derived from a comprehensive analysis and evaluation of historical test data and corresponding historical test results from the three months prior to this test. Those skilled in the art will understand that the method described in this invention can determine the above-mentioned parameters in the following ways: selecting the value with the highest proportion based on the data distribution as the preset standard parameter; using weighted summation to obtain the value as the preset standard parameter; substituting each historical data point into a specific formula and using the value obtained by that formula as the preset standard parameter; or other selection methods, as long as the method described in this invention can clearly define different specific situations in the single-item judgment process through the obtained values.

[0058] Please see Figure 1 , Figure 2 , Figure 3 as well as Figure 4 The figures shown are: a structural schematic diagram of the adaptive variable diameter screw conveyor according to an embodiment of the present invention; a flowchart of a process for determining whether the conveying of the adaptive variable diameter screw conveyor meets a preset standard based on the resilience rate of the fiber material according to an embodiment of the present invention; a flowchart of an adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard according to an embodiment of the present invention; and a flowchart of a method for using the adaptive variable diameter screw conveyor according to an embodiment of the present invention.

[0059] On one hand, embodiments of the present invention provide an adaptive variable diameter screw conveyor, comprising:

[0060] The machine body 1 has a feed hopper 2 located at the upper part of one end of the machine body 1, and a discharge port 3 located at the lower part of the end of the machine body 1 away from the feed hopper 2. A spiral shaft 4 is installed through the inside of the machine body 1, and spiral blades 5 are provided on the surface of the spiral shaft 4. A drive motor 6 is provided at the end of the spiral shaft 4 near the feed hopper 2. The end of the machine body 1 with the feed hopper 2 is referred to as the feed end, and the end of the machine body 1 with the discharge port 3 is referred to as the discharge end. The diameter of the spiral blades 5 gradually decreases from the feed end to the discharge end.

[0061] The data acquisition module includes a fiber material volume acquisition unit respectively disposed on the feed hopper 2 and the discharge port 3, a spiral shaft sound signal acquisition unit disposed on the outer shell 1, and a current acquisition unit disposed on the drive motor 6.

[0062] The control module, which is connected to the data acquisition module, is used to determine whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the rebound rate of the fiber material at the discharge port 3; and to make a secondary determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft 4 within a preset period.

[0063] The correction module is connected to the control module and the drive motor 6 respectively, and is used to determine the speed adjustment strategy for the drive motor 6 based on the peak ratio difference and to determine the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor 6.

[0064] It should be noted that the data in this embodiment are all results obtained through preliminary experiments before this test using the method described in this invention. Each preset value can be adjusted according to the specific application, as long as the method described in this invention can clearly define different specific situations in the single-item judgment process through the acquired values. The preset values ​​set in this embodiment are all obtained from preliminary experiments, including the correction coefficients, which were also selected through experimental verification.

[0065] Specifically, the spiral blade 5 extends axially along the spiral shaft 4, and its outer diameter changes continuously from the feed end to the discharge end. The diameter of each spiral blade 5 is smaller than that of the previous spiral blade 5 (i.e., the diameter closer to the feed end), and the diameter difference between two adjacent spiral blades is a constant value, forming a variable diameter spiral conveying surface. In this embodiment, the constant value is selected as 3mm.

[0066] In this embodiment, the fiber material volume acquisition unit is a three-dimensional laser scanner; the spiral shaft sound signal acquisition unit is a sound sensor; and the current acquisition unit is a Hall current sensor.

[0067] Specifically, there are no restrictions on the specific structure of the control module and the correction module. They themselves and their units can be composed of logic components, including field-programmable components, computers, or microprocessors in computers.

[0068] Specifically, the control module determines whether the conveying of the adaptive variable diameter screw conveyor meets a preset standard based on the resilience rate of the fiber material at the discharge port 3.

[0069] If the resilience of the fiber material is less than the first preset fiber material resilience of 0.40, it is determined that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard. The correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor 6.

[0070] If the resilience of the fiber material is greater than or equal to the first preset fiber material resilience and less than the second preset fiber material resilience, then the conveying of the adaptive variable diameter screw conveyor is determined to meet the preset standard.

[0071] If the resilience of the fiber material is greater than or equal to the second preset fiber material resilience of 0.60, it is determined that the conveying of the adaptive variable diameter screw conveyor meets the preset standard, and the conveying of the adaptive variable diameter screw conveyor meets the preset standard again based on the percentage of abnormal sound peak of the screw shaft 4 within the preset period.

[0072] Specifically, the first preset fiber material resilience rate ranges from (0.15, 0.45) to (0.50, 0.70). Preferably, the first preset fiber material resilience rate is selected as 0.40, and the second preset fiber material resilience rate is selected as 0.60.

[0073] Specifically, fibrous materials are characterized by their elastic deformation capability: when subjected to the compressive force of a screw conveyor, they undergo plastic deformation (volume reduction), but due to the hydrogen bonding and mechanical entanglement between fibers, they exhibit elastic rebound after the pressure is released. The rebound rate essentially reflects the integrity of the fiber structure; a low rebound rate indicates excessive compressive force leading to fiber breakage and structural damage, resulting in a loss of elastic recovery capability; a high rebound rate indicates insufficient compressive force, meaning the gaps between fibers are not effectively compressed (excessive elastic recovery space).

[0074] Specifically, the process of obtaining the resilience of the fiber material includes:

[0075] A fiber material volume acquisition unit is provided in the feed hopper 2 and the discharge port 3 respectively;

[0076] The first volume of the fiber material in the feed hopper 2 and the second volume of the fiber material after compression at the discharge port 3 are obtained by measurement.

[0077] The compressed volume of the fibrous material is the difference between the first volume of the material and the second volume of the fibrous material;

[0078] After the fiber material is discharged from the outlet 3 and left to stand for a first preset time of 12 minutes, the volume of the material after rebound stabilization is measured and recorded as the third volume.

[0079] The rebound volume of the fiber material is the difference between the third volume and the second volume;

[0080] The resilience rate of the fiber material is the ratio of the rebound volume of the fiber material to the compressed volume of the fiber material.

[0081] Specifically, the control module makes a secondary determination, based on the percentage of abnormal sound peaks of the screw shaft 4 within a preset 10-minute period, whether the conveying of the adaptive variable diameter screw conveyor meets a preset standard.

[0082] If the percentage of abnormal sound peaks is less than a preset percentage of 0.08, then the conveying of the adaptive variable diameter screw conveyor is determined to meet the preset standard.

[0083] If the percentage of abnormal sound peaks is greater than or equal to the preset percentage, it is determined that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard. The control module controls the feeding to stop, and after a second preset time of 3 minutes, the correction module executes the speed adjustment strategy for the drive motor 6.

[0084] Specifically, when the control module determines that the conveying does not meet the standard and stops feeding, some fibrous material may still remain in the conveying pipe of the screw conveyor. If the speed adjustment of the drive motor 6 is executed immediately, the residual material will cause abnormal load on the screw shaft 4. The second preset delay is set to allow the screw conveyor to enter a stable state after the feeding stops, so as to avoid the residual material interfering with the subsequent adjustment strategy.

[0085] In this embodiment, the preset percentage is 0.08, but the above value is not limited to this, and those skilled in the art can adjust the value according to actual needs.

[0086] Specifically, the percentage of abnormal sound peaks is the ratio between the number of abnormal sound peaks and the total number of sound peaks within a preset period. Abnormal sound peaks are sound peaks that exceed the preset sound peak by 92dB.

[0087] Specifically, the process by which the correction module determines the speed adjustment strategy for the drive motor 6 based on the peak percentage difference includes:

[0088] The peak percentage difference is compared with the first preset peak percentage difference of 0.02 and the second preset peak percentage difference of 0.05 respectively;

[0089] If the peak percentage difference is less than the first preset peak percentage difference, the speed of the drive motor 6 will be reduced to the second preset speed of 720 rpm.

[0090] If the peak percentage difference is greater than or equal to the first preset peak percentage difference and less than the second preset peak percentage difference, then the speed of the drive motor 6 is first reduced to zero and maintained at zero speed for a third preset duration of 30 seconds, then the speed of the drive motor 6 is reversed and the reverse speed is increased to a third preset speed of 540 rpm and maintained at the third preset speed for a fourth preset duration of 90 seconds, then the speed of the drive motor 6 is forward and the forward speed is increased to a fourth preset speed of 810 rpm, while the control module controls the resumption of feeding.

[0091] If the peak percentage difference is greater than or equal to the second preset peak percentage difference, the system will stop and an alarm will be issued.

[0092] The peak percentage difference is the difference between the peak percentage of the abnormal sound and the preset percentage.

[0093] Specifically, the first preset peak percentage difference is selected as 0.02, and the second preset peak percentage difference is selected as 0.05. However, the above values ​​are not limited to these, and those skilled in the art can adjust the values ​​according to actual needs.

[0094] Specifically, the second preset speed is 80%-85% of the first preset speed; the third preset speed is 50%-70% of the first preset speed; and the fourth preset speed is 88%-90% of the first preset speed. The second preset speed is in the same direction as the first preset speed, the third preset speed is in the opposite direction to the first preset speed, and the fourth preset speed is in the same direction as the first preset speed. In this embodiment, the second preset speed is 80% of the first preset speed, which is 720 rpm; the third preset speed is 60% of the first preset speed, which is 540 rpm; and the fourth preset speed is 90% of the first preset speed, which is 810 rpm.

[0095] Specifically, after the drive motor 6 drops to zero speed, it is left to stand still. This is to loosen the fibrous material in the screw conveyor and reduce the impact when it reverses.

[0096] Specifically, the correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor 6.

[0097] If the current fluctuation value is less than the preset current fluctuation value of 5A, the amount of fiber material input is reduced according to the difference between the preset current fluctuation value and the current fluctuation value.

[0098] If the current fluctuation value is greater than or equal to the preset current fluctuation value, the machine will stop and an alarm will be issued.

[0099] Specifically, the reduction in the amount of fiber material input is positively correlated with the difference between the preset current fluctuation value and the current fluctuation value. The positive correlation can be linear or nonlinear. The slope of the linear positive correlation is not specifically limited. It can be understood that the greater the difference between the preset current fluctuation value and the current fluctuation value, the greater the reduction in the amount of fiber material input.

[0100] Specifically, the current fluctuation value of the drive motor 6 is the absolute value of the difference between the current of the drive motor 6 and the preset current 22A.

[0101] In this embodiment, the preset current fluctuation value is selected as 5A, but the above value is not limited to this, and those skilled in the art can also adjust the value according to actual needs.

[0102] On the other hand, embodiments of the present invention provide a method of using an adaptive variable diameter screw conveyor, including:

[0103] Step S1: Start the drive motor 6 to the first preset speed of 900 rpm, so that the spiral shaft 4 drives the spiral blades 5 to rotate, and feed fiber material into the feed hopper 2. During the transportation of fiber material, the data acquisition module collects the sound signal of the spiral shaft 4 during operation and the current of the drive motor 6. The fiber material is transported to the discharge port 3 through the spiral blades 5. The fiber material volume acquisition unit of the data acquisition module collects the first volume of fiber material in the feed hopper 2, the second volume of fiber material after compression in the discharge port 3, and the third volume of fiber material after standing for a first preset time.

[0104] Step S2: The control module calculates the resilience rate of the fiber material and determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the resilience rate. Then, the control module makes a second determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft 4 within a preset period. If the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the percentage of abnormal sound peaks of the screw shaft 4 within a preset period, the correction module determines the speed adjustment strategy for the drive motor 6 based on the difference in peak percentages.

[0105] Step S3: When the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the fiber material rebound rate, the correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor 6.

[0106] Step S4: After the conveying task is completed, control the drive motor 6 to stop running.

[0107] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

[0108] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An adaptive variable diameter screw conveyor, characterized in that, include: The machine body has an outer casing, a feed hopper located at the upper part of one end of the outer casing, and a discharge port located at the lower part of the outer casing at the end away from the feed hopper. A spiral shaft is installed through the interior of the outer casing, and spiral blades are provided on the surface of the spiral shaft. A drive motor is located at the end of the spiral shaft near the feed hopper. The end of the outer casing with the feed hopper is referred to as the feed end, and the end of the outer casing with the discharge port is referred to as the discharge end. The diameter of the spiral blades gradually decreases from the feed end to the discharge end. The data acquisition module includes a fiber material volume acquisition unit respectively disposed in the feed hopper and the discharge port, a spiral shaft sound signal acquisition unit disposed in the outer shell of the machine body, and a current acquisition unit disposed in the drive motor. The control module, which is connected to the data acquisition module, is used to determine whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the rebound rate of the fiber material at the discharge port; and to make a secondary determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period. The correction module is connected to the control module and the drive motor respectively, and is used to determine the speed adjustment strategy for the drive motor based on the peak ratio difference and to determine the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor. The control module determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the comparison result that the rebound rate of the fiber material at the discharge port is greater than or equal to the first preset fiber material rebound rate. When the rebound rate of the fiber material is greater than or equal to the second preset fiber material rebound rate, the control module determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard again based on the proportion of abnormal sound peak value of the screw shaft within the preset period. The first preset fiber material rebound rate is less than the second preset fiber material rebound rate. The control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the comparison result that the rebound rate of the fiber material at the discharge port is less than the first preset fiber material rebound rate. The correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor. The process of obtaining the resilience of the fiber material includes: A fiber material volume acquisition unit is provided in the feed hopper and the discharge port respectively; The first volume of the fiber material in the feed hopper and the second volume of the fiber material after compression at the discharge port are obtained by measurement. The compressed volume of the fibrous material is the difference between the first volume of the material and the second volume of the fibrous material; After the fiber material is discharged from the outlet and left to stand for a first preset time, the volume of the material after rebound and stabilization is measured and recorded as the third volume. The rebound volume of the fiber material is the difference between the third volume and the second volume; The resilience rate of the fiber material is the ratio of the rebound volume of the fiber material to the compressed volume of the fiber material.

2. The adaptive variable diameter screw conveyor according to claim 1, characterized in that, The control module makes a secondary determination, based on the percentage of abnormal sound peaks of the screw shaft within a preset period, whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard. If the percentage of abnormal sound peaks is less than the preset percentage, then the conveying of the adaptive variable diameter screw conveyor is determined to meet the preset standard. If the percentage of abnormal sound peaks is greater than or equal to the preset percentage, it is determined that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard. The control module controls the feeding to stop, and after a second preset time delay, the correction module executes a speed adjustment strategy for the drive motor.

3. The adaptive variable diameter screw conveyor according to claim 2, characterized in that, The percentage of abnormal sound peaks is the ratio between the number of abnormal sound peaks and the total number of sound peaks within a preset period. Abnormal sound peaks are sound peaks that exceed the preset sound peak.

4. The adaptive variable diameter screw conveyor according to claim 3, characterized in that, The process by which the correction module determines the speed adjustment strategy for the drive motor based on the peak percentage difference includes: The peak percentage difference is compared with the first preset peak percentage difference and the second preset peak percentage difference, respectively; If the peak percentage difference is less than the first preset peak percentage difference, the speed of the drive motor will be reduced to the second preset speed. If the peak percentage difference is greater than or equal to the first preset peak percentage difference and less than the second preset peak percentage difference, then the speed of the drive motor is first reduced to zero and maintained at zero speed for a third preset time, then the speed of the drive motor is reversed and the reverse speed is increased to a third preset speed and maintained at the third preset speed for a fourth preset time, then the speed of the drive motor is forward and the forward speed is increased to a fourth preset speed, while the control module controls the resumption of feeding. If the peak percentage difference is greater than or equal to the second preset peak percentage difference, the system will stop and an alarm will be issued. The peak percentage difference is the difference between the peak percentage of the abnormal sound and the preset percentage.

5. The adaptive variable diameter screw conveyor according to claim 4, characterized in that, The correction module determines the adjustment strategy when the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the current fluctuation value of the drive motor. If the current fluctuation value is less than the preset current fluctuation value, the amount of fiber material input is reduced according to the difference between the preset current fluctuation value and the current fluctuation value. If the current fluctuation value is greater than or equal to the preset current fluctuation value, the machine will stop and an alarm will be issued.

6. The adaptive variable diameter screw conveyor according to claim 5, characterized in that, The current fluctuation value of the drive motor is the absolute value of the difference between the current of the drive motor and the preset current.

7. A method of using the adaptive variable diameter screw conveyor according to any one of claims 1-6, characterized in that, include: The drive motor is started to the first preset speed, causing the spiral shaft to drive the spiral blades to rotate and feed fiber material into the feed hopper. During the transportation of the fiber material, the data acquisition module collects the sound signal of the spiral shaft during operation and the current of the drive motor. The fiber material is conveyed to the discharge port through the spiral blades. The fiber material volume acquisition unit of the data acquisition module collects the first volume of the fiber material in the feed hopper, the second volume of the fiber material after compression at the discharge port, and the third volume of the fiber material after standing for a first preset time. The control module calculates the resilience rate of the fiber material and determines whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the resilience rate. Then, the control module makes a second determination on whether the conveying of the adaptive variable diameter screw conveyor meets the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period. If the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the percentage of abnormal sound peaks of the screw shaft within a preset period, the correction module determines the speed adjustment strategy for the drive motor based on the difference in peak percentages. When the control module determines that the conveying of the adaptive variable diameter screw conveyor does not meet the preset standard based on the resilience rate of the fiber material, the correction module determines the adjustment strategy for the conveying of the adaptive variable diameter screw conveyor when it does not meet the preset standard based on the current fluctuation value of the drive motor. Once the delivery task is completed, the drive motor is stopped.

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