Aluminum alloy classification device and method based on double-excitation eddy current array sensor

Abstract

The invention relates to a non-magnetic metal classification technology, in particular to an aluminum alloy classification device and method based on a double-excitation eddy current array sensor, and the device comprises a belt conveyor, two stand columns, two cross beams, a transparent supporting plate, a correlation type photoelectric switch, an eddy current array sensor, a laser distance measuring sensor, a signal generator, a signal conditioner and an upper computer; the two stand columns are fixed to the ground on the two sides of the belt conveyor respectively. The head ends of the two cross beams are fixed to the upper ends of the two stand columns respectively. The transparent supporting plate is horizontally fixed between the tail ends of the two cross beams; an emitter and a receiver of the correlation type photoelectric switch are respectively fixed on the side surfaces of the two upright posts; the eddy current array sensor comprises four coils which are horizontally fixed on the upper surface of the transparent supporting plate and are arranged in a rhombus shape; the laser distance measuring sensor is fixed on the upper surface of the transparent supporting plate. The problem that the classification accuracy is low when an existing non-magnetic metal classification technology is applied to aluminum alloy classification is solved, and the method is suitable for aluminum alloy classification.

Description

Technical Field

[0001] The present invention relates to a non-magnetic metal classification technology, in particular to an aluminum alloy classification device and method based on a dual-excitation eddy current array sensor. Background Art

[0002] In the process of sorting scrap metals, magnetic metals can be sorted out relatively easily, while the remaining non-magnetic metals usually have a higher recycling value. At present, in the recycling process of non-magnetic metals, the eddy current method is gradually being used in metal classification due to its fast response speed and non-destructive characteristics. However, in actual applications, this method has a low response sensitivity to conductivity differences, so it can only accurately classify different metals with significant differences in conductivity. For different types of aluminum alloys with similar conductivity, the classification accuracy of this method is low. Based on this, it is necessary to invent an aluminum alloy classification device and method based on a dual-excitation eddy current array sensor to solve the problem of low classification accuracy of existing non-magnetic metal classification technology when applied to aluminum alloy classification. Summary of the Invention

[0003] In order to solve the problem of low classification accuracy of existing non-magnetic metal classification technology when applied to aluminum alloy classification, the present invention provides an aluminum alloy classification device and method based on a dual-excitation eddy current array sensor.

[0004] The present invention is achieved by adopting the following technical solutions:

[0005] An aluminum alloy sorting device based on a dual-excitation eddy current array sensor includes a belt conveyor, two columns, two beams, a transparent support plate, a beam-type photoelectric switch, an eddy current array sensor, a laser ranging sensor, a signal generator, a signal conditioner, and a host computer;

[0006] The belt conveyor is fixed horizontally on the ground; two columns are fixed on the ground on both sides of the belt conveyor; the head ends of the two beams are fixed to the upper ends of the two columns, and both beams are located above the belt conveyor; the transparent support plate is fixed horizontally between the tail ends of the two beams;

[0007] The transmitter and receiver of the beam-type photoelectric switch are respectively fixed to the sides of the two pillars; the eddy current array sensor includes four coils fixed horizontally to the upper surface of the transparent support plate and arranged in a diamond shape; the two coils located at the left and right vertices of the diamond shape serve as the two excitation coils; the two coils located at the front and rear vertices of the diamond shape serve as the two receiving coils; the laser ranging sensor is fixed to the upper surface of the transparent support plate;

[0008] The host computer is electrically connected to the two excitation coils through a signal generator; the two receiving coils are electrically connected to the host computer through a signal conditioner; the receiver of the beam type photoelectric switch and the laser distance sensor are electrically connected to the host computer.

[0009] Furthermore, the four coils are cylindrical hollow coils of the same size, with an inner diameter of 3 mm, an outer diameter of 9.6 mm, a wire diameter of 0.01 mm, a height of 0.05 mm, and 100 turns.

[0010] A method for aluminum alloy classification based on a dual-excitation eddy current array sensor is implemented based on an aluminum alloy classification device based on a dual-excitation eddy current array sensor described in the present invention. The method is implemented using the following steps:

[0011] Step 1: Start the through-beam photoelectric switch, and the transmitter of the through-beam photoelectric switch emits a light beam to the receiver;

[0012] Step 2: placing the aluminum alloy sample to be classified on the upper surface of the conveyor belt of the belt conveyor, and the aluminum alloy sample moves along the conveyor belt of the belt conveyor;

[0013] Step 3: When the aluminum alloy sample moves between the two columns, the light beam is blocked by the aluminum alloy sample, and the receiver of the through-beam photoelectric switch outputs a switch signal. The host computer controls the laser ranging sensor and the signal generator to start according to the switch signal. Then, the laser ranging sensor measures the lift-off height and transmits the measurement result to the host computer. The lift-off height refers to the distance between the eddy current array sensor and the aluminum alloy sample. At the same time, the signal generator outputs an excitation signal. The excitation signal is transmitted to the two excitation coils, so that eddy currents are induced in the aluminum alloy sample, thereby inducing two mutual induction signals in the two receiving coils. The two mutual induction signals are conditioned by the signal conditioner and transmitted to the host computer.

[0014] Step 4: The host computer collects the amplitude points of the two mutual inductance signals, selects the maximum amplitude point from the amplitude points of the two mutual inductance signals, and then calculates the phase value of the maximum amplitude point as the characteristic value of the aluminum alloy sample;

[0015] Step 5: Determine the characteristic coordinate point of the aluminum alloy sample with the lift-off height as the abscissa and the characteristic value of the aluminum alloy sample as the ordinate; then, respectively calculate the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the first characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the second characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the third characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the fourth characteristic curve, and the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the fifth characteristic curve;

[0016] The first characteristic curve is: ;in, The value range is 3mm~7mm;

[0017] The second characteristic curve is: ;in, The value range is 3mm~7mm;

[0018] The third characteristic curve is: ;in, The value range is 3mm~7mm;

[0019] The fourth characteristic curve is: ;in, The value range is 3mm~7mm;

[0020] The fifth characteristic curve is: ;in, The value range is 3mm~7mm;

[0021] Step 6: Based on the calculation results of step 5, determine the material of the aluminum alloy sample and classify the aluminum alloy sample accordingly; the specific determination rules are as follows:

[0022] When the longitudinal distance between the characteristic coordinate point of the aluminum alloy sample and the first characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample is determined to be AL2017;

[0023] When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the second characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample is determined to be AL5052;

[0024] When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the third characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample is determined to be AL6061;

[0025] When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the fourth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample is determined to be AL3A12;

[0026] When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample to the fifth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample is determined to be AL1100.

[0027] Furthermore, in step 4, the calculation formula of the phase value of the maximum amplitude point is as follows:

[0028] ;

[0029] Where: Indicates the phase value of the maximum amplitude point; The imaginary part represents the maximum amplitude point; Represents the real part of the maximum amplitude point.

[0030] Furthermore, the excitation signal is a sine wave signal, the excitation frequency thereof is 40 kHz, and the excitation voltage thereof is 1V.

[0031] Compared to existing non-magnetic metal classification technologies, the aluminum alloy classification device and method based on a dual-excitation eddy current array sensor described in this invention utilizes dual-excitation coils to generate two mutual induction signals. The phase value of the maximum amplitude point of the two mutual induction signals serves as the classification basis, significantly improving sensitivity to conductivity differences. Consequently, the present invention achieves higher classification accuracy for aluminum alloys of similar conductivity. Experiments have shown that when applied to aluminum alloy classification, the present invention achieves a classification accuracy of up to 97.2%.

[0032] The present invention effectively solves the problem of low classification accuracy of existing non-magnetic metal classification technology when applied to aluminum alloy classification, and is suitable for the classification of aluminum alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a partial structural schematic diagram of the device of the present invention.

[0034] Figure 2 yes Figure 1 Top view of .

[0035] Figure 3 yes Figure 1 Right view of .

[0036] Figure 4 It is another partial structural schematic diagram of the device of the present invention.

[0037] Figure 5 It is a schematic diagram of the first to fifth characteristic curves in the method of the present invention.

[0038] In the figure: 1-belt conveyor, 2-column, 3-crossbeam, 4-transparent support plate, 501-transmitter of the through-beam photoelectric switch, 502-receiver of the through-beam photoelectric switch, 601-excitation coil, 602-receiving coil, 7-laser ranging sensor, 8-signal generator, 9-signal conditioner, 10-host computer, 11-aluminum alloy sample. DETAILED DESCRIPTION

[0039] An aluminum alloy sorting device based on a dual-excitation eddy current array sensor includes a belt conveyor 1, two columns 2, two beams 3, a transparent support plate 4, a beam-to-beam photoelectric switch, an eddy current array sensor, a laser ranging sensor 7, a signal generator 8, a signal conditioner 9, and a host computer 10;

[0040] The belt conveyor 1 is fixed horizontally on the ground; two columns 2 are fixed on the ground on both sides of the belt conveyor 1; the head ends of two cross beams 3 are fixed to the upper ends of the two columns 2, and the two cross beams 3 are located above the belt conveyor 1; a transparent support plate 4 is fixed horizontally between the tail ends of the two cross beams 3;

[0041] The transmitter 501 and receiver 502 of the beam-type photoelectric switch are respectively fixed to the sides of the two pillars 2; the eddy current array sensor includes four coils fixed horizontally to the upper surface of the transparent support plate 4 and arranged in a diamond shape; the two coils located at the left and right vertices of the diamond shape serve as two excitation coils 601; the two coils located at the front and rear vertices of the diamond shape serve as two receiving coils 602; the laser ranging sensor 7 is fixed to the upper surface of the transparent support plate 4;

[0042] The host computer 10 is electrically connected to the two excitation coils 601 through the signal generator 8; the two receiving coils 602 are electrically connected to the host computer 10 through the signal conditioner 9; the receiver 502 of the beam photoelectric switch and the laser ranging sensor 7 are both electrically connected to the host computer 10.

[0043] The four coils are cylindrical hollow coils of the same size, with an inner diameter of 3 mm, an outer diameter of 9.6 mm, a wire diameter of 0.01 mm, a height of 0.05 mm, and 100 turns.

[0044] A method for aluminum alloy classification based on a dual-excitation eddy current array sensor is implemented based on an aluminum alloy classification device based on a dual-excitation eddy current array sensor described in the present invention. The method is implemented using the following steps:

[0045] Step 1: Start the beam-transmitting photoelectric switch. The transmitter 501 of the beam-transmitting photoelectric switch transmits a light beam to the receiver 502.

[0046] Step 2: placing the aluminum alloy sample 11 to be classified on the upper surface of the conveyor belt of the belt conveyor 1, and the aluminum alloy sample 11 moves along the conveyor belt of the belt conveyor 1;

[0047] Step 3: When the aluminum alloy sample 11 moves between the two pillars 2, the light beam is blocked by the aluminum alloy sample 11, and the receiver 502 of the beam-type photoelectric switch outputs a switch signal. The host computer 10 controls the laser ranging sensor 7 and the signal generator 8 to start according to the switch signal; then, the laser ranging sensor 7 measures the lift-off height and transmits the measurement result to the host computer 10; the lift-off height refers to the distance between the eddy current array sensor and the aluminum alloy sample 11; at the same time, the signal generator 8 outputs an excitation signal; the excitation signal is transmitted to the two excitation coils 601, so that eddy currents are induced in the aluminum alloy sample 11, thereby inducing two mutual induction signals in the two receiving coils 602; the two mutual induction signals are conditioned by the signal conditioner 9 and transmitted to the host computer 10;

[0048] Step 4: The host computer 10 collects the amplitude points of the two mutual inductance signals, selects the maximum amplitude point from the amplitude points of the two mutual inductance signals, and then calculates the phase value of the maximum amplitude point as the characteristic value of the aluminum alloy sample 11;

[0049] Step 5: Determine the characteristic coordinate point of the aluminum alloy sample 11 with the lift-off height as the horizontal coordinate and the characteristic value of the aluminum alloy sample 11 as the vertical coordinate; then, respectively calculate the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the first characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the second characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the third characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the fourth characteristic curve, and the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the fifth characteristic curve;

[0050] The first characteristic curve is: ;in, The value range is 3mm~7mm;

[0051] The second characteristic curve is: ;in, The value range is 3mm~7mm;

[0052] The third characteristic curve is: ;in, The value range is 3mm~7mm;

[0053] The fourth characteristic curve is: ;in, The value range is 3mm~7mm;

[0054] The fifth characteristic curve is: ;in, The value range is 3mm~7mm;

[0055] Step 6: Based on the calculation results of step 5, determine the material of the aluminum alloy sample 11, and classify the aluminum alloy sample 11 accordingly; the specific determination rules are as follows:

[0056] When the longitudinal distance between the characteristic coordinate point of the aluminum alloy sample 11 and the first characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample 11 is determined to be AL2017;

[0057] When the longitudinal distance between the characteristic coordinate point of the aluminum alloy sample 11 and the second characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample 11 is determined to be AL5052;

[0058] When the longitudinal distance between the characteristic coordinate point of the aluminum alloy sample 11 and the third characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample 11 is determined to be AL6061;

[0059] When the longitudinal distance between the characteristic coordinate point of the aluminum alloy sample 11 and the fourth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample 11 is determined to be AL3A12;

[0060] When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample 11 to the fifth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample 11 is determined to be AL1100.

[0061] In step 4, the calculation formula of the phase value of the maximum amplitude point is as follows:

[0062] ;

[0063] Where: Indicates the phase value of the maximum amplitude point; The imaginary part represents the maximum amplitude point; Represents the real part of the maximum amplitude point.

[0064] The excitation signal is a sine wave signal with an excitation frequency of 40kHz and an excitation voltage of 1V.

[0065] In a specific implementation, the conveyor belt speed of the belt conveyor 1 is 1 cm / s; the transparent support plate 4 is made of acrylic; the horizontal distance between the two excitation coils 601 is 11 mm; and the horizontal distance between the two receiving coils 602 is 18 mm.

[0066] Although specific embodiments of the present invention have been described above, those skilled in the art will appreciate that these are merely illustrative and that the scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, and such changes and modifications are intended to fall within the scope of the present invention.

Claims

1. An aluminum alloy classification device based on a dual-excitation eddy current array sensor, characterized by: It includes a belt conveyor (1), two upright columns (2), two crossbeams (3), a transparent support plate (4), a beam-type photoelectric switch, an eddy current array sensor, a laser distance sensor (7), a signal generator (8), a signal conditioner (9), and a host computer (10); The belt conveyor (1) is fixed horizontally on the ground; the two upright posts (2) are respectively fixed on the ground on both sides of the belt conveyor (1); the head ends of the two cross beams (3) are respectively fixed to the upper ends of the two upright posts (2), and the two cross beams (3) are both located above the belt conveyor (1); the transparent support plate (4) is fixed horizontally between the tail ends of the two cross beams (3); The transmitter (501) and receiver (502) of the beam-type photoelectric switch are respectively fixed to the sides of the two upright posts (2); the eddy current array sensor comprises four coils fixed horizontally to the upper surface of the transparent support plate (4) and arranged in a diamond shape; the two coils located at the left and right vertices of the diamond shape serve as two excitation coils (601); the two coils located at the front and rear vertices of the diamond shape serve as two receiving coils (602); the laser distance sensor (7) is fixed to the upper surface of the transparent support plate (4); The host computer (10) is electrically connected to the two excitation coils (601) via the signal generator (8); the two receiving coils (602) are both electrically connected to the host computer (10) via the signal conditioner (9); and the receiver (502) of the beam-type photoelectric switch and the laser distance sensor (7) are both electrically connected to the host computer (10).

2. The aluminum alloy classification device based on a dual-excitation eddy current array sensor according to claim 1, characterized in that: The four coils are cylindrical hollow coils of the same size, with an inner diameter of 3 mm, an outer diameter of 9.6 mm, a wire diameter of 0.01 mm, a height of 0.05 mm, and 100 turns.

3. A method for aluminum alloy classification based on a dual-excitation eddy current array sensor, the method being implemented based on the aluminum alloy classification device based on a dual-excitation eddy current array sensor as claimed in claim 1, characterized in that: This method is implemented using the following steps: Step 1: activating the beam-type photoelectric switch, wherein the transmitter (501) of the beam-type photoelectric switch transmits a light beam to the receiver (502); Step 2: placing the aluminum alloy sample (11) to be classified on the upper surface of the conveyor belt of the belt conveyor (1), and the aluminum alloy sample (11) moves along the conveyor belt of the belt conveyor (1); Step 3: When the aluminum alloy sample (11) moves between the two columns (2), the light beam is blocked by the aluminum alloy sample (11), and the receiver (502) of the beam-type photoelectric switch outputs a switch signal, and the host computer (10) controls the laser distance sensor (7) and the signal generator (8) to start according to the switch signal; then, the laser distance sensor (7) measures the lift-off height and transmits the measurement result to the host computer (10); the lift-off height refers to the distance between the eddy current array sensor and the aluminum alloy sample (11); at the same time, the signal generator (8) outputs an excitation signal; the excitation signal is transmitted to the two excitation coils (601), so that eddy currents are induced in the aluminum alloy sample (11), thereby inducing two mutual induction signals in the two receiving coils (602); the two mutual induction signals are conditioned by the signal conditioner (9) and transmitted to the host computer (10); Step 4: The host computer (10) collects the amplitude points of the two mutual inductance signals, selects the maximum amplitude point from the amplitude points of the two mutual inductance signals, and then calculates the phase value of the maximum amplitude point as the characteristic value of the aluminum alloy sample (11); Step 5: Determine the characteristic coordinate point of the aluminum alloy sample (11) with the lift-off height as the horizontal coordinate and the characteristic value of the aluminum alloy sample (11) as the vertical coordinate; then, respectively calculate the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the first characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the second characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the third characteristic curve, the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the fourth characteristic curve, and the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the fifth characteristic curve; The first characteristic curve is: ;in, The value range is 3mm~7mm; The second characteristic curve is: ;in, The value range is 3mm~7mm; The third characteristic curve is: ;in, The value range is 3mm~7mm; The fourth characteristic curve is: ;in, The value range is 3mm~7mm; The fifth characteristic curve is: ;in, The value range is 3mm~7mm; Step 6: Based on the calculation results of step 5, determine the material of the aluminum alloy sample (11), and classify the aluminum alloy sample (11); the specific determination rules are as follows: When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the first characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample (11) is determined to be AL2017; When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the second characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample (11) is determined to be AL5052; When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the third characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample (11) is determined to be AL6061; When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the fourth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample (11) is determined to be AL3A12; When the longitudinal distance from the characteristic coordinate point of the aluminum alloy sample (11) to the fifth characteristic curve is less than or equal to 0.01, the material of the aluminum alloy sample (11) is determined to be AL1100.

4. The aluminum alloy classification method based on a dual-excitation eddy current array sensor according to claim 3 is characterized in that: In step 4, the calculation formula of the phase value of the maximum amplitude point is as follows: ； Where: Indicates the phase value of the maximum amplitude point; The imaginary part represents the maximum amplitude point; Represents the real part of the maximum amplitude point.

5. The aluminum alloy classification method based on a dual-excitation eddy current array sensor according to claim 3, characterized in that: The excitation signal is a sine wave signal with an excitation frequency of 40kHz and an excitation voltage of 1V.

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