A continuous sorting device for defective cored lotus seeds based on online sound recognition

Abstract

The present invention discloses a device for continuously sorting defective cored lotus seeds based on online sound recognition. The device comprises a lotus seed conveying roller chain, an airflow nozzle, a sound collection system, and a sorting execution system. The lotus seed conveying roller chain carries the cored lotus seeds continuously through a curtain-like airflow ejected from the airflow nozzle. Because the core holes of good cored lotus seeds are coaxial with the lotus seed axis, while the core holes of defective cored lotus seeds are offset from the axis, the airflow conditions differ, thereby generating differential sound response signals. A sound recognition program identifies the sound response signals online to determine the category of the lotus seeds being tested and makes a sorting decision. The advantages of the present invention are as follows: lotus seeds are identified and sorted while continuously advancing along the chain, resulting in high sorting efficiency; a flat nozzle is used to eject a curtain-like airflow to sort lotus seeds of different sizes, eliminating the need to adjust the nozzle position according to seed size; and a micro-pressure airflow that causes minimal disturbance to the lotus seeds is used, eliminating the need to compress the lotus seeds during classification and testing, thus streamlining the device structure.

Description

Technical Field

[0001] The present invention relates to the field of material classification based on sound recognition, in particular to a device for continuously sorting defective cored lotus seeds based on online sound recognition. Background Art

[0002] Lotus seeds are an economic crop, often used as a functional food ingredient and in Traditional Chinese Medicine. Coring is a crucial step in lotus seed production, aimed at removing the bitter pith inside the seeds. A common method for coring lotus seeds is to create a through-hole along the axis of the lotus seed to allow the pith to escape. However, during this through-hole processing, the coring hole can easily become misaligned with the axis of the lotus seed, resulting in defective cored lotus seeds, making it difficult to remove the pith. Defective cored lotus seeds have low appearance quality and are prone to mixing ingredients and causing mildew, impacting the overall quality and economic value of lotus seed products. Therefore, automated sorting of defective cored lotus seeds is essential.

[0003] Traditional manual sorting suffers from low efficiency, high workload, and the tendency to fatigue and errors. Widely used color sorting technology, however, struggles to distinguish between good and defective cored lotus seeds that differ only in the location of the core holes. In recent years, automated cored lotus seed sorting technology based on sound signal classification has emerged. Patent publication number CN116944069B discloses a cored lotus seed defective sorting device based on airflow excitation and audio recognition. This technical solution utilizes a feed chain that carries the lotus seeds in intermittent stepping motion. When the lotus seeds enter the sorting and inspection station, a lotus seed pressing and centering mechanism presses the lotus seeds against the feed chain, keeping them stationary. Simultaneously, the height of an air needle is adjusted so that its axis is coaxial with the lotus seed axis. The air needle then releases air toward the end face of the lotus seed. Due to the difference in the location of the core holes, the airflow generates different response signals on good and defective cored lotus seeds. Based on this, an audio classification program is used to identify and classify good and defective cored lotus seeds.

[0004] However, this technical solution has the following limitations: 1. The feed chain moves forward step by step, carrying the lotus seeds through each station, thus enabling only intermittent sorting. 2. During sorting and testing, both the air needle and the lotus seeds must be stationary and compressed, preventing continuous sorting. 3. During sorting and testing, the air needle axis must be aligned with the lotus seed axis using a lotus seed compression and centering mechanism to ensure consistent sorting of lotus seeds of varying sizes. These limitations limit the sorting efficiency of this technical solution, and its implementation is relatively complex. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a continuous sorting device for defective cored lotus seeds based on online sound recognition, which further improves the working efficiency of cored lotus seeds sorting through continuous operation.

[0006] The present invention adopts a technical solution: a device for continuously sorting defective cored lotus seeds based on online sound recognition, comprising a frame, a feeding system, a lotus seed conveying roller chain, an airflow nozzle, a sound collection system, and a sorting execution system; the feeding system, the sound collection system, the airflow nozzle, and the sorting execution system are arranged in sequence along the forward direction of the lotus seed conveying roller chain; the airflow nozzle is located on one side of the lotus seed conveying roller chain, and continuously ejects airflow, and the lotus seed conveying roller chain carries the cored lotus seeds that have been rolled and positioned to continuously move and pass through the airflow;

[0007] The axis of the airflow nozzle is parallel to the roller axis of the lotus seed conveying roller chain; the outlet cross-section of the airflow nozzle is flat, and the outlet cross-section covers the height variation range of the axis of the cored lotus seeds in the height direction to accommodate the sorting of cored lotus seeds of different sizes;

[0008] The sound collection system includes a microphone and a soundproof box. The airflow nozzle and microphone are located inside the soundproof box, and the lotus seed conveying roller chain passes through the soundproof box. When the airflow acts on the end surface of the continuously moving cored lotus seeds, a sound response signal is generated. Because the cored holes on good cored lotus seeds are coaxial with the axis of the good cored lotus seeds, while the cored holes on defective cored lotus seeds are skewed from the axis of the defective cored lotus seeds, the airflow conditions are different, so the sound response signals corresponding to good cored lotus seeds and defective cored lotus seeds differ. The sound response signals are collected online in real time by the microphone and input into the control system.

[0009] The control system is provided with a sound recognition program, which determines the category of the cored lotus seeds currently being detected based on the sound response signal and makes a sorting decision at the same time. If the cored lotus seeds currently being detected are defective, they are allowed to continue to move forward along the lotus seed conveying roller chain. When passing the position of the material removal device in the sorting execution system, they are removed by the material removal device and fall into a defective product collection box. If the cored lotus seeds currently being detected are good, they are allowed to continue to move forward along the lotus seed conveying roller chain until they fall into the good product collection box.

[0010] The feeding system is used to supply cored lotus seeds one by one into each link space on the lotus seed conveying roller chain; a color code sensor is also provided on one side of the lotus seed conveying roller chain between the feeding system and the air flow nozzle for detecting whether there are cored lotus seeds in the link space.

[0011] As a further optimization of this solution, the sound recognition program is built based on a deep learning model, which is used to automatically extract the features of the sound response signal and identify and classify it; the sound response signal includes two categories: signals corresponding to good cored lotus seeds and signals corresponding to defective cored lotus seeds.

[0012] As a further optimization of this solution, the deep learning model is a one-dimensional convolutional neural network model, which recognizes and classifies one-dimensional sound response signals; the deep learning model can also be a two-dimensional convolutional neural network model, which recognizes and classifies two-dimensional time-frequency spectrograms obtained after time-frequency conversion of the one-dimensional sound response signals.

[0013] As a further optimization of this solution, the outlet cross-section of the airflow nozzle is one of rectangular, oblong, and elliptical, and its height dimension is greater than its width dimension; and the airflow is a curtain-like airflow.

[0014] As a further optimization of this solution, the parameter values ​​of the airflow are determined based on the standard that the airflow does not destroy the rolling posture of the cored lotus seeds on the lotus seed conveying roller chain.

[0015] As a further optimization of this solution, the air pressure of the airflow is less than or equal to 0.03 MPa.

[0016] As a further optimization of this solution, a groove is provided on the circumferential surface of the roller, and the chain link space is located between the grooves of two adjacent rollers for accommodating a cored lotus seed.

[0017] As a further optimization of this solution, a chain bracket is provided under the lotus seed conveying roller chain; when the lotus seed conveying roller chain moves forward, the roller rotates in the chain bracket, thereby driving the cored lotus seeds in the chain link space to rotate, and adjusting the axis of the cored lotus seeds to be parallel to the axis of the roller before the cored lotus seeds reach the position of the airflow nozzle, thereby achieving rolling straightening and positioning.

[0018] As a further optimization of this solution, the material removal method of the material removal device is one of air blowing, air suction, mechanical striking, and mechanical sweeping.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. The lotus seed conveying roller chain operates continuously during the sorting process, improving sorting efficiency; 2. A flat nozzle is used to continuously spray a curtain-like airflow of a certain width, eliminating the need for a nozzle axis height adjustment mechanism to achieve sorting of cored lotus seeds of different sizes; 3. The cored lotus seeds being inspected pass through the airflow continuously, completing detection and classification online in real time as they move forward without pausing, thereby improving sorting efficiency; 4. The use of a micro-pressure airflow prevents the cored lotus seeds from being moved along the chain, eliminating the need for an additional cored lotus seed pressing mechanism and streamlining the device's mechanical structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the continuous sorting principle diagram of the present invention;

[0021] Figure 2 This is a comparison diagram of good and defective cored lotus seeds of the present invention when passing through air flow;

[0022] Figure 3 is a schematic diagram of an air flow nozzle of the present invention;

[0023] Figure 4 This invention Figure 3 AA cross-section in;

[0024] Figure 5 Schematic diagram of the curtain-like airflow ejected by the airflow nozzle of the present invention adapted to the needs of cored lotus seeds of different sizes;

[0025] Figure 6 It is a front view of the continuous sorting device of the present invention;

[0026] Figure 7 This invention Figure 6 A local enlarged view of point B in FIG;

[0027] Figure 8 This invention Figure 7 CC cross-section diagram in;

[0028] Figure 9 is a top view of the continuous sorting device of the present invention;

[0029] Figure 10 This invention Figure 9 A local enlarged view of point D in FIG;

[0030] Figure 11 It is a left side view of the continuous sorting device of the present invention.

[0031] The main components in the figure include: 1 frame; 2 feeding system; 3 lotus seed conveying roller chain; 3-1 roller; 3-1-1 groove; 3-1-2 chain link space; 3-2 chain bracket; 3-3 color mark sensor; 4 air flow nozzle; 4-1 air flow; 4-2 outlet section; 5 sound collection system; 5-1 microphone; 5-1-1 sound response signal; 5-2 sound insulation box; 6 sorting execution system; 6-1 material removal device; 6-2 defective product collection box; 6-3 good product collection box; 7 cored lotus seeds; 7-1 good cored lotus seeds; 7-1a cored hole; 7-2 defective cored lotus seeds; 7-2a cored hole; 8 control system. DETAILED DESCRIPTION

[0032] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings.

[0033] like Figure 6 、 Figures 9-11As shown, the present invention includes a frame 1, a feeding system 2, a lotus seed conveying roller chain 3, an airflow nozzle 4, a sound collection system 5, and a sorting execution system 6. The feeding system 2, the sound collection system 5, the airflow nozzle 4, and the sorting execution system 6 are arranged in sequence along the forward direction of the lotus seed conveying roller chain 3.

[0034] The feeding system 2 is used to supply cored lotus seeds 7 one by one into each link space 3-1-2 on the lotus seed conveying roller chain 3. A color code sensor 3-3 is also provided on one side of the lotus seed conveying roller chain 3 between the feeding system 2 and the air flow nozzle 4 to detect whether there are cored lotus seeds 7 in the link space 3-1-2.

[0035] like Figure 1 、 Figure 2 、 Figure 6 、 Figure 9 As shown, the airflow nozzle 4 is located on one side of the lotus seed conveying roller chain 3. The airflow nozzle 4 continuously ejects airflow 4-1, and the lotus seed conveying roller chain 3, carrying the cored lotus seeds 7 that have been rolled and positioned, continuously moves through the airflow 4-1. The parameters of the airflow 4-1 are determined based on the standard that the airflow 4-1 does not disrupt the rolled and positioned posture of the cored lotus seeds 7 on the lotus seed conveying roller chain 3. The air pressure of the airflow 4-1 is less than or equal to 0.03 MPa.

[0036] like Figure 1-Figure 5 As shown, the axis of the air flow nozzle 4 is parallel to the axis of the roller 3-1 of the lotus seed conveying roller chain 3; the outlet cross-section 4-2 of the air flow nozzle 4 is flat, and the outlet cross-section 4-2 covers the axis height variation range of the cored lotus seeds 7 in the height direction to adapt to the sorting of cored lotus seeds 7 of different sizes.

[0037] like Figure 1 、 Figure 2 、 Figure 6 、 Figure 9 As shown, the sound collection system 5 includes a microphone 5-1 and a soundproof box 5-2, the airflow nozzle 4 and the microphone 5-1 are located inside the soundproof box 5-2, and the lotus seed conveying roller chain 3 passes through the soundproof box 5-2; when the airflow 4-1 acts on the end face of the continuously moving cored lotus seed 7, a sound response signal 5-1-1 will be generated. Since the cored hole 7-1a on the good cored lotus seed 7-1 is coaxial with the axis of the good cored lotus seed 7-1, while the cored hole 7-2a on the defective cored lotus seed 7-2 is tilted from the axis of the defective cored lotus seed 7-2, the airflow 4-1 passes through different conditions, so there is a difference between the sound response signal 5-1-1 corresponding to the good cored lotus seed 7-1 and the sound response signal 5-1-1 corresponding to the defective cored lotus seed 7-2; the sound response signal 5-1-1 is collected online in real time by the microphone 5-1 and input into the control system 8.

[0038] like Figure 6 、 Figure 9 、 Figure 11 As shown, the control system 8 is provided with a sound recognition program, and the sound recognition program determines the category of the currently detected cored lotus seeds 7 according to the sound response signal 5-1-1, and makes a sorting decision at the same time; if the currently detected cored lotus seeds 7 are defective, they continue to move forward with the lotus seed conveying roller chain 3, and when passing the position of the material removal device 6-1 in the sorting execution system 6, they are removed by the material removal device 6-1 and fall into the defective product collection box 6-2; if the currently detected cored lotus seeds 7 are good, they continue to move forward with the lotus seed conveying roller chain 3 until they fall into the good product collection box 6-3.

[0039] The sound recognition program is built based on a deep learning model and is used to automatically extract features from the sound response signal 5-1-1 and identify and classify it. The sound response signal 5-1-1 includes two types: signals corresponding to good, cored lotus seeds 7-1 and signals corresponding to defective, cored lotus seeds 7-2. The deep learning model is a one-dimensional convolutional neural network model that identifies and classifies the one-dimensional sound response signal 5-1-1. The deep learning model can also be a two-dimensional convolutional neural network model that identifies and classifies the two-dimensional time-frequency spectrum obtained by time-frequency conversion of the one-dimensional sound response signal 5-1-1.

[0040] like Figure 4 、 Figure 5 As shown, the outlet cross section 4-2 of the airflow nozzle 4 is one of rectangular, oblong, and elliptical, and its height dimension is greater than its width dimension; the airflow 4-1 is a curtain-like airflow.

[0041] like Figure 10 As shown, a groove 3-1-1 is provided on the circumferential surface of the roller 3-1, and the link space 3-1-2 is located between the grooves 3-1-1 of two adjacent rollers 3-1 for accommodating a cored lotus seed 7.

[0042] like Figure 6-Figure 9 As shown, a chain bracket 3-2 is provided below the lotus seed conveying roller chain 3; when the lotus seed conveying roller chain 3 moves forward, the roller 3-1 rotates in the chain bracket 3-2, thereby driving the cored lotus seeds 7 in the chain link space 3-1-2 to rotate, and adjusting the axis of the cored lotus seeds 7 to be parallel to the axis of the roller 3-1 before the cored lotus seeds 7 reach the position of the air flow nozzle 4, thereby achieving rolling straightening and positioning.

[0043] like Figure 6 、 Figure 9 、 Figure 11 As shown, the material removal method of the material removal device 6-1 is one of air blowing, air suction, mechanical striking, and mechanical sweeping.

[0044] The present invention operates as follows: a feeding system 2 feeds cored lotus seeds 7 one by one into the link spaces 3-1-2 of a lotus seed conveying roller chain 3. As the lotus seed conveying roller chain 3 advances, its rollers 3-1 rotate within the chain brackets 3-2 positioned below it, causing the cored lotus seeds 7 in the link spaces 3-1-2 to rotate. Before the cored lotus seeds 7 reach the position of the airflow nozzle 4, the axis of the cored lotus seeds 7 is aligned parallel to the axis of the rollers 3-1, completing the rolling and positioning process. During this process, a color code sensor 3-3 detects and confirms whether cored lotus seeds 7 are present in the link spaces 3-1-2 being passed through. An airflow nozzle 4 with a flattened outlet cross-section 4-2, located on one side of the lotus seed conveying roller chain 3, continuously ejects a curtain-like airflow 4-1. Subsequently, the lotus seed conveying roller chain 3, carrying the cored lotus seeds 7 after rolling and positioning, continuously moves through the airflow 4-1. During this process, the airflow 4-1 does not disrupt the straightened rolling posture of the cored lotus seeds 7 on the lotus seed conveying roller chain 3. When the airflow 4-1 acts on the end face of the continuously moving cored lotus seeds 7, an acoustic response signal 5-1-1 is generated. Because the cored holes 7-1a on the acceptable cored lotus seeds 7-1 are coaxial with the axis of the acceptable cored lotus seeds 7-1, while the cored holes 7-2a on the defective cored lotus seeds 7-2 are offset from the axis of the defective cored lotus seeds 7-2, the airflow 4-1 passes through different conditions, resulting in a difference between the acoustic response signals 5-1-1 corresponding to the acceptable cored lotus seeds 7-1 and the acoustic response signals 5-1-1 corresponding to the defective cored lotus seeds 7-2. The acoustic response signals 5-1-1 are collected online and in real time by the microphone 5-1 inside the soundproof box 5-2 and input into the control system 8. The control system 8 is provided with a sound recognition program, which determines the category of the currently detected cored lotus seeds 7 according to the sound response signal 5-1-1 and makes a sorting decision at the same time; if the currently detected cored lotus seeds 7 are defective, they continue to move forward with the lotus seed conveying roller chain 3, and when passing the position of the material removal device 6-1 in the sorting execution system 6, they are removed by the material removal device 6-1 and fall into the defective product collection box 6-2; if the currently detected cored lotus seeds 7 are good products, they continue to move forward with the lotus seed conveying roller chain 3 until they fall into the good product collection box 6-3, and the sorting is completed at this time.

Claims

1. A device for continuously sorting defective cored lotus seeds based on online sound recognition, comprising a frame (1), a feeding system (2), a lotus seed conveying roller chain (3), an airflow nozzle (4), a sound collection system (5), and a sorting execution system (6); characterized in that: The feeding system (2), the sound collection system (5), the airflow nozzle (4), and the sorting execution system (6) are arranged in sequence along the forward direction of the lotus seed conveying roller chain (3); the airflow nozzle (4) is located on one side of the lotus seed conveying roller chain (3), and the airflow nozzle (4) continuously ejects airflow (4-1). The lotus seed conveying roller chain (3) carries the cored lotus seeds (7) that have been rolled and positioned, and continuously moves and passes through the airflow (4-1); The axis of the airflow nozzle (4) is parallel to the axis of the roller (3-1) of the lotus seed conveying roller chain (3); the outlet cross section (4-2) of the airflow nozzle (4) is flat, and the outlet cross section (4-2) covers the height variation range of the axis of the cored lotus seeds (7) in the height direction to adapt to the sorting of cored lotus seeds (7) of different sizes; The sound collection system (5) includes a microphone (5-1) and a soundproof box (5-2). The airflow nozzle (4) and the microphone (5-1) are located inside the soundproof box (5-2). The lotus seed conveying roller chain (3) passes through the soundproof box (5-2). When the airflow (4-1) acts on the end face of the continuously moving cored lotus seed (7), a sound response signal (5-1-1) is generated. Since the cored hole (7-1a) on the cored lotus seed (7-1) is in contact with the cored lotus seed (7-1), the cored lotus seed (7-1) is in contact with the cored lotus seed (7-1). 7-1) are coaxial, while the cored hole (7-2a) on the defective cored lotus seed (7-2) is tilted from the axis of the defective cored lotus seed (7-2), and the airflow (4-1) passes through different conditions, so there is a difference between the sound response signal (5-1-1) corresponding to the good cored lotus seed (7-1) and the sound response signal (5-1-1) corresponding to the defective cored lotus seed (7-2); the sound response signal (5-1-1) is collected online in real time by the microphone (5-1) and input into the control system (8); The control system (8) is provided with a sound recognition program, and the sound recognition program determines the category of the currently detected cored lotus seeds (7) according to the sound response signal (5-1-1), and makes a sorting decision at the same time; if the currently detected cored lotus seeds (7) are defective products, they are allowed to continue to move forward along with the lotus seed conveying roller chain (3), and when passing through the position of the material removal device (6-1) in the sorting execution system (6), they are removed by the material removal device (6-1) and fall into the defective product collection box (6-2); if the currently detected cored lotus seeds (7) are good products, they are allowed to continue to move forward along with the lotus seed conveying roller chain (3) until they fall into the good product collection box (6-3); The feeding system (2) is used to supply cored lotus seeds (7) one by one into each link space (3-1-2) on the lotus seed conveying roller chain (3); a color code sensor (3-3) is also provided on one side of the lotus seed conveying roller chain (3) between the feeding system (2) and the air flow nozzle (4) for detecting whether the cored lotus seeds (7) are present in the link space (3-1-2).

2. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: The sound recognition program is constructed based on a deep learning model and is used to automatically extract the features of the sound response signal (5-1-1) and identify and classify it; the sound response signal (5-1-1) includes two types: a signal corresponding to good cored lotus seeds (7-1) and a signal corresponding to defective cored lotus seeds (7-2).

3. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 2, characterized in that: The deep learning model is a one-dimensional convolutional neural network model, which recognizes and classifies the one-dimensional sound response signal (5-1-1); the deep learning model can also be a two-dimensional convolutional neural network model, which recognizes and classifies the two-dimensional time-frequency spectrum obtained by time-frequency conversion of the one-dimensional sound response signal (5-1-1).

4. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: The outlet cross-section (4-2) of the airflow nozzle (4) is one of a rectangle, an oblong, and an ellipse, and its height dimension is greater than its width dimension; the airflow (4-1) is a curtain-like airflow.

5. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: The parameter values ​​of the airflow (4-1) are determined based on the standard that the airflow (4-1) does not damage the rolling posture of the cored lotus seeds (7) on the lotus seed conveying roller chain (3).

6. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 5, wherein: The air pressure of the airflow (4-1) is less than or equal to 0.03 MPa.

7. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: A groove (3-1-1) is provided on the circumferential surface of the roller (3-1), and the link space (3-1-2) is located between the grooves (3-1-1) of two adjacent rollers (3-1) and is used to accommodate a cored lotus seed (7).

8. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: A chain bracket (3-2) is provided below the lotus seed conveying roller chain (3); when the lotus seed conveying roller chain (3) moves forward, the roller (3-1) rotates in the chain bracket (3-2), thereby driving the cored lotus seeds (7) in the chain link space (3-1-2) to rotate, and adjusting the axis of the cored lotus seeds (7) to be parallel to the axis of the roller (3-1) before the cored lotus seeds (7) reach the position of the air flow nozzle (4), thereby achieving rolling alignment and positioning.

9. The device for continuously sorting defective cored lotus seeds based on online sound recognition according to claim 1, characterized in that: The material removal device (6-1) is used in a material removal mode selected from the group consisting of air blowing, air suction, mechanical striking, and mechanical sweeping.

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